MC

5581_d8d2

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 6.9, pKa2 = 10.0.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 4.2 Incorrect pI = 8.4 Correct pI = 11.9 Incorrect MC

b2b4_0381

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 6.2, pKa2 = 10.0.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 4.2 Incorrect pI = 8.1 Correct pI = 12.1 Incorrect MC

8307_56b7

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 7.1, pKa2 = 10.0.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 4.6 Incorrect pI = 8.6 Correct pI = 12.3 Incorrect MC

876f_a80b

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 4.7, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 3.2 Correct pI = 7.7 Incorrect pI = 12.1 Incorrect MC

c852_c365

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 5.7, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 3.9 Incorrect pI = 7.6 Correct pI = 11.9 Incorrect MC

1f8c_fef2

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 6.3, pKa2 = 10.5.

The isoelectric point (pI) is closest to which value?

pI = 1.3 Incorrect pI = 4.1 Incorrect pI = 8.4 Correct pI = 11.9 Incorrect MC

9cbf_8eab

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 8.0, pKa2 = 9.9.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 5.2 Incorrect pI = 8.9 Correct pI = 11.8 Incorrect MC

c77e_da3b

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 5.8, pKa2 = 10.1.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 4.2 Incorrect pI = 7.9 Correct pI = 12.2 Incorrect MC

86fd_fb98

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 4.5, pKa2 = 9.2.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 3.3 Correct pI = 6.5 Incorrect pI = 11.4 Incorrect MC

6670_32c7

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 7.2, pKa2 = 10.3.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 4.5 Incorrect pI = 8.8 Correct pI = 12.2 Incorrect MC

982d_3998

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 8.0, pKa2 = 9.6.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 4.9 Incorrect pI = 8.8 Correct pI = 11.6 Incorrect MC

f30a_03f1

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 5.5, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.7 Incorrect pI = 7.6 Correct pI = 11.5 Incorrect MC

dbbc_8ede

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 6.0, pKa2 = 9.3.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.8 Incorrect pI = 7.7 Correct pI = 11.3 Incorrect MC

6ac6_ae2a

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 4.8, pKa2 = 9.2.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.5 Correct pI = 6.8 Incorrect pI = 11.7 Incorrect MC

32d6_f2c1

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 7.8, pKa2 = 9.3.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 4.7 Incorrect pI = 8.6 Correct pI = 11.8 Incorrect MC

da6e_1989

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 5.0, pKa2 = 10.3.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.5 Correct pI = 7.4 Incorrect pI = 11.8 Incorrect MC

0804_8425

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 3.9, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.0 Correct pI = 6.8 Incorrect pI = 12.1 Incorrect MC

3119_4343

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 7.1, pKa2 = 9.6.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.9 Incorrect pI = 8.3 Correct pI = 12.1 Incorrect MC

0f24_0246

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 4.1, pKa2 = 9.4.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 3.2 Correct pI = 7.0 Incorrect pI = 11.4 Incorrect MC

1bf0_2923

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 6.3, pKa2 = 9.8.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 4.5 Incorrect pI = 8.1 Correct pI = 11.9 Incorrect MC

b3c5_425a

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 3.8, pKa2 = 10.5.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 2.8 Correct pI = 7.2 Incorrect pI = 11.9 Incorrect MC

fd28_d43a

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 7.9, pKa2 = 9.1.

The isoelectric point (pI) is closest to which value?

pI = 1.3 Incorrect pI = 5.2 Incorrect pI = 8.5 Correct pI = 11.5 Incorrect MC

1fab_c269

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 3.7, pKa2 = 10.4.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.0 Correct pI = 7.4 Incorrect pI = 12.1 Incorrect MC

e748_2845

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 7.8, pKa2 = 10.0.

The isoelectric point (pI) is closest to which value?

pI = 0.6 Incorrect pI = 4.6 Incorrect pI = 8.9 Correct pI = 12.3 Incorrect MC

fd41_c7b9

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 4.3, pKa2 = 10.5.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.1 Correct pI = 7.4 Incorrect pI = 12.2 Incorrect MC

d301_b926

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 4.4, pKa2 = 10.3.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 3.2 Correct pI = 7.3 Incorrect pI = 11.8 Incorrect MC

8bb3_0b2a

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 6.4, pKa2 = 9.2.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 4.0 Incorrect pI = 7.8 Correct pI = 11.9 Incorrect MC

9403_4786

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 5.8, pKa2 = 10.4.

The isoelectric point (pI) is closest to which value?

pI = 0.6 Incorrect pI = 4.0 Incorrect pI = 8.1 Correct pI = 12.4 Incorrect MC

a136_ec79

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 6.9, pKa2 = 9.4.

The isoelectric point (pI) is closest to which value?

pI = 1.3 Incorrect pI = 4.4 Incorrect pI = 8.2 Correct pI = 11.9 Incorrect MC

834d_7e60

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 4.5, pKa2 = 9.9.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 3.4 Correct pI = 7.0 Incorrect pI = 11.8 Incorrect MC

287b_0a15

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 5.8, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.7 Incorrect pI = 7.7 Correct pI = 11.8 Incorrect MC

fbfd_622a

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 3.8, pKa2 = 10.4.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.0 Correct pI = 7.4 Incorrect pI = 12.4 Incorrect MC

605d_763c

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 5.0, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 3.8 Correct pI = 7.2 Incorrect pI = 11.4 Incorrect MC

26cc_c04e

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 5.9, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.0 Incorrect pI = 7.8 Correct pI = 12.0 Incorrect MC

0801_6d30

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 5.7, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.1 Incorrect pI = 7.9 Correct pI = 12.4 Incorrect MC

a5f5_acb0

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 3.6, pKa2 = 9.9.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 2.9 Correct pI = 7.0 Incorrect pI = 11.6 Incorrect MC

4ca3_efc6

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 6.6, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.6 Incorrect pI = 8.1 Correct pI = 11.7 Incorrect MC

0324_cce6

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 4.7, pKa2 = 9.1.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.4 Correct pI = 7.2 Incorrect pI = 11.6 Incorrect MC

9204_08ba

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 4.7, pKa2 = 9.6.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.5 Correct pI = 7.2 Incorrect pI = 11.9 Incorrect MC

4e64_0e94

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 4.7, pKa2 = 9.6.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.5 Correct pI = 6.9 Incorrect pI = 11.8 Incorrect MC

eafe_0c63

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 4.8, pKa2 = 9.1.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.4 Correct pI = 7.2 Incorrect pI = 11.5 Incorrect MC

901e_9924

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 7.7, pKa2 = 9.9.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.7 Incorrect pI = 8.8 Correct pI = 12.1 Incorrect MC

804a_faea

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 3.5, pKa2 = 9.8.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 2.7 Correct pI = 6.5 Incorrect pI = 11.7 Incorrect MC

f8d2_b31b

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 6.4, pKa2 = 10.3.

The isoelectric point (pI) is closest to which value?

pI = 1.6 Incorrect pI = 4.2 Incorrect pI = 8.4 Correct pI = 11.8 Incorrect MC

1278_9f1f

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 3.8, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 2.8 Correct pI = 6.7 Incorrect pI = 11.7 Incorrect MC

da65_cdf8

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 6.2, pKa2 = 9.2.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 4.4 Incorrect pI = 7.7 Correct pI = 11.7 Incorrect MC

ed84_8fdb

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 7.2, pKa2 = 10.5.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 4.8 Incorrect pI = 8.8 Correct pI = 12.3 Incorrect MC

1e9c_3dcb

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 4.9, pKa2 = 10.5.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.4 Correct pI = 8.0 Incorrect pI = 12.2 Incorrect MC

5f31_fb9e

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 6.8, pKa2 = 9.0.

The isoelectric point (pI) is closest to which value?

pI = 1.3 Incorrect pI = 4.2 Incorrect pI = 7.9 Correct pI = 11.2 Incorrect MC

5eb7_e85d

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 6.4, pKa2 = 9.9.

The isoelectric point (pI) is closest to which value?

pI = 0.7 Incorrect pI = 4.3 Incorrect pI = 8.2 Correct pI = 11.6 Incorrect MC

8906_9082

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 4.2, pKa2 = 9.8.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.2 Correct pI = 7.2 Incorrect pI = 11.8 Incorrect MC

f913_f843

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 5.8, pKa2 = 9.6.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.2 Incorrect pI = 7.7 Correct pI = 11.8 Incorrect MC

7769_2620

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 4.4, pKa2 = 9.8.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 3.2 Correct pI = 6.9 Incorrect pI = 12.0 Incorrect MC

7217_fe72

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 4.7, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 3.5 Correct pI = 6.9 Incorrect pI = 11.8 Incorrect MC

b2a2_6caf

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 4.9, pKa2 = 10.1.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.4 Correct pI = 7.5 Incorrect pI = 12.4 Incorrect MC

a0bb_6c47

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 7.7, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 5.2 Incorrect pI = 8.6 Correct pI = 11.9 Incorrect MC

e3f4_0d31

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 7.8, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 4.6 Incorrect pI = 8.8 Correct pI = 11.9 Incorrect MC

22f7_6854

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 6.8, pKa2 = 10.0.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 4.5 Incorrect pI = 8.4 Correct pI = 12.0 Incorrect MC

0ee0_1704

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 5.6, pKa2 = 9.3.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.6 Incorrect pI = 7.5 Correct pI = 11.7 Incorrect MC

be9e_5cfe

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 4.3, pKa2 = 9.6.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.2 Correct pI = 6.6 Incorrect pI = 12.0 Incorrect MC

5f77_22b8

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 4.9, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 3.7 Correct pI = 7.6 Incorrect pI = 11.7 Incorrect MC

414c_2b0e

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 4.2, pKa2 = 9.8.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.3 Correct pI = 6.9 Incorrect pI = 11.6 Incorrect MC

66b6_de7b

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 6.1, pKa2 = 9.3.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.8 Incorrect pI = 7.7 Correct pI = 11.6 Incorrect MC

37dd_fa34

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 3.6, pKa2 = 10.1.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 2.8 Correct pI = 7.0 Incorrect pI = 12.2 Incorrect MC

caf9_1113

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 6.9, pKa2 = 9.1.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 4.9 Incorrect pI = 8.0 Correct pI = 11.6 Incorrect MC

b044_feea

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 3.6, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 1.3 Incorrect pI = 3.0 Correct pI = 6.6 Incorrect pI = 11.9 Incorrect MC

6d63_59fa

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 4.6, pKa2 = 10.3.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.5 Correct pI = 7.2 Incorrect pI = 12.1 Incorrect MC

95ce_76d5

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 3.6, pKa2 = 10.1.

The isoelectric point (pI) is closest to which value?

pI = 1.6 Incorrect pI = 3.0 Correct pI = 6.8 Incorrect pI = 12.1 Incorrect MC

50d1_2cce

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 8.0, pKa2 = 9.0.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 5.2 Incorrect pI = 8.5 Correct pI = 11.2 Incorrect MC

dcb7_3b1b

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 6.8, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 4.5 Incorrect pI = 8.2 Correct pI = 11.8 Incorrect MC

bedb_ca6d

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 3.8, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 0.7 Incorrect pI = 2.8 Correct pI = 6.5 Incorrect pI = 11.7 Incorrect MC

7d20_6dc7

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 6.7, pKa2 = 9.1.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.8 Incorrect pI = 7.9 Correct pI = 11.9 Incorrect MC

4984_452a

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 4.6, pKa2 = 9.0.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.2 Correct pI = 6.6 Incorrect pI = 11.4 Incorrect MC

6e06_5b52

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 4.9, pKa2 = 9.1.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.7 Correct pI = 7.3 Incorrect pI = 11.8 Incorrect MC

066b_b825

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 4.7, pKa2 = 9.4.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.5 Correct pI = 7.3 Incorrect pI = 11.7 Incorrect MC

6072_e632

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 4.0, pKa2 = 9.1.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.0 Correct pI = 6.2 Incorrect pI = 11.5 Incorrect MC

5ab6_68e0

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 6.9, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 1.5 Incorrect pI = 4.9 Incorrect pI = 8.3 Correct pI = 11.9 Incorrect MC

e8aa_072e

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 5.6, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 4.1 Incorrect pI = 7.5 Correct pI = 11.8 Incorrect MC

3b62_0d7b

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 4.7, pKa2 = 10.0.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.4 Correct pI = 7.3 Incorrect pI = 12.2 Incorrect MC

8eac_c7a0

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 3.8, pKa2 = 9.0.

The isoelectric point (pI) is closest to which value?

pI = 0.7 Incorrect pI = 2.9 Correct pI = 6.6 Incorrect pI = 11.3 Incorrect MC

1cc7_c38b

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 3.9, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.0 Correct pI = 7.0 Incorrect pI = 12.4 Incorrect MC

cc43_cd5d

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 7.7, pKa2 = 9.6.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 5.0 Incorrect pI = 8.7 Correct pI = 11.7 Incorrect MC

4c22_542e

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 4.6, pKa2 = 9.0.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.3 Correct pI = 7.0 Incorrect pI = 11.2 Incorrect MC

305a_7eb9

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 3.9, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 3.2 Correct pI = 6.7 Incorrect pI = 11.5 Incorrect MC

fb3e_50d5

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 6.9, pKa2 = 9.3.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 4.2 Incorrect pI = 8.1 Correct pI = 11.6 Incorrect MC

0928_5049

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 4.5, pKa2 = 9.8.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.1 Correct pI = 6.9 Incorrect pI = 11.7 Incorrect MC

144d_5368

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 7.0, pKa2 = 10.0.

The isoelectric point (pI) is closest to which value?

pI = 1.3 Incorrect pI = 4.7 Incorrect pI = 8.5 Correct pI = 12.0 Incorrect MC

5968_9370

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 7.6, pKa2 = 10.3.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 4.5 Incorrect pI = 8.9 Correct pI = 12.2 Incorrect MC

2fea_8e45

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 7.6, pKa2 = 10.3.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 5.2 Incorrect pI = 8.9 Correct pI = 12.5 Incorrect MC

c8ce_2cae

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 6.2, pKa2 = 9.3.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 4.1 Incorrect pI = 7.8 Correct pI = 11.8 Incorrect MC

28c6_ce44

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 4.9, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 3.6 Correct pI = 7.4 Incorrect pI = 11.8 Incorrect MC

8334_52bc

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 4.9, pKa2 = 10.1.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.7 Correct pI = 7.5 Incorrect pI = 12.2 Incorrect MC

b660_2102

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 4.5, pKa2 = 10.5.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.2 Correct pI = 7.6 Incorrect pI = 11.9 Incorrect MC

e755_77e8

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 6.9, pKa2 = 9.8.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 4.1 Incorrect pI = 8.4 Correct pI = 11.6 Incorrect MC

8065_a991

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 7.8, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 5.1 Incorrect pI = 8.8 Correct pI = 12.0 Incorrect MC

9b94_35e3

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 4.6, pKa2 = 9.4.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 3.3 Correct pI = 7.0 Incorrect pI = 11.4 Incorrect MC

43e2_a687

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 7.1, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 5.0 Incorrect pI = 8.6 Correct pI = 12.1 Incorrect MC

ba18_4740

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 4.3, pKa2 = 9.4.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 3.1 Correct pI = 7.1 Incorrect pI = 11.8 Incorrect MC

cf7e_963b

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 4.0, pKa2 = 9.8.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 2.9 Correct pI = 7.0 Incorrect pI = 12.0 Incorrect MC

35d1_8849

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 4.9, pKa2 = 9.2.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 3.5 Correct pI = 7.0 Incorrect pI = 11.4 Incorrect MC

0620_10d8

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 7.4, pKa2 = 10.1.

The isoelectric point (pI) is closest to which value?

pI = 0.7 Incorrect pI = 4.8 Incorrect pI = 8.8 Correct pI = 12.2 Incorrect MC

ea99_a1d1

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 6.3, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 4.5 Incorrect pI = 8.2 Correct pI = 12.4 Incorrect MC

1438_e6e9

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 5.5, pKa2 = 9.3.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.8 Incorrect pI = 7.4 Correct pI = 12.0 Incorrect MC

6707_8958

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 6.1, pKa2 = 9.1.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 4.5 Incorrect pI = 7.6 Correct pI = 11.5 Incorrect MC

61b2_830a

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 3.8, pKa2 = 10.0.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 2.9 Correct pI = 6.6 Incorrect pI = 11.8 Incorrect MC

80b0_6ff4

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 5.0, pKa2 = 9.4.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.6 Correct pI = 7.1 Incorrect pI = 12.0 Incorrect MC

af8d_2418

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 4.1, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.2 Correct pI = 6.7 Incorrect pI = 11.7 Incorrect MC

9b92_a5e3

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 7.0, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 4.4 Incorrect pI = 8.6 Correct pI = 12.2 Incorrect MC

6653_3b82

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 3.5, pKa2 = 10.0.

The isoelectric point (pI) is closest to which value?

pI = 0.7 Incorrect pI = 2.8 Correct pI = 6.5 Incorrect pI = 11.8 Incorrect MC

a313_23ac

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 7.4, pKa2 = 9.2.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 5.1 Incorrect pI = 8.3 Correct pI = 11.7 Incorrect MC

24d3_e144

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 8.0, pKa2 = 10.0.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 5.2 Incorrect pI = 9.0 Correct pI = 12.0 Incorrect MC

1ac4_9e1c

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 4.9, pKa2 = 10.0.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.6 Correct pI = 7.5 Incorrect pI = 11.7 Incorrect MC

0009_a680

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 7.1, pKa2 = 9.4.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 5.0 Incorrect pI = 8.2 Correct pI = 11.9 Incorrect MC

4d54_5022

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 7.1, pKa2 = 9.0.

The isoelectric point (pI) is closest to which value?

pI = 0.6 Incorrect pI = 4.3 Incorrect pI = 8.1 Correct pI = 11.5 Incorrect MC

635b_7581

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 4.5, pKa2 = 10.1.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.4 Correct pI = 7.0 Incorrect pI = 12.2 Incorrect MC

884c_cd96

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 3.7, pKa2 = 9.3.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 3.0 Correct pI = 6.6 Incorrect pI = 11.5 Incorrect MC

b6c5_d6dd

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 4.9, pKa2 = 9.0.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.5 Correct pI = 6.8 Incorrect pI = 11.8 Incorrect MC

0fb2_d0ea

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 4.8, pKa2 = 10.1.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 3.5 Correct pI = 7.5 Incorrect pI = 11.9 Incorrect MC

e3d7_1aaf

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 7.9, pKa2 = 9.6.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 5.3 Incorrect pI = 8.8 Correct pI = 11.8 Incorrect MC

65d2_4cf9

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 4.5, pKa2 = 9.2.

The isoelectric point (pI) is closest to which value?

pI = 1.5 Incorrect pI = 3.5 Correct pI = 6.8 Incorrect pI = 11.9 Incorrect MC

b3a9_db30

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 7.6, pKa2 = 10.3.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 5.3 Incorrect pI = 8.9 Correct pI = 12.3 Incorrect MC

86c1_21c3

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 7.2, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.5 Incorrect pI = 8.3 Correct pI = 11.4 Incorrect MC

a900_f324

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 6.8, pKa2 = 10.3.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 4.7 Incorrect pI = 8.6 Correct pI = 12.5 Incorrect MC

aca7_9325

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 5.7, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.0 Incorrect pI = 7.7 Correct pI = 11.8 Incorrect MC

67ba_9ec3

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 7.0, pKa2 = 9.8.

The isoelectric point (pI) is closest to which value?

pI = 1.3 Incorrect pI = 4.8 Incorrect pI = 8.4 Correct pI = 12.2 Incorrect MC

8e0b_7875

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 7.0, pKa2 = 9.8.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 4.5 Incorrect pI = 8.4 Correct pI = 12.1 Incorrect MC

6616_5dde

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 4.9, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 0.7 Incorrect pI = 3.5 Correct pI = 7.5 Incorrect pI = 11.9 Incorrect MC

f967_ebdf

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 5.7, pKa2 = 9.1.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.0 Incorrect pI = 7.4 Correct pI = 11.8 Incorrect MC

eb16_ffba

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 7.9, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 1.3 Incorrect pI = 5.2 Incorrect pI = 8.8 Correct pI = 11.5 Incorrect MC

ffeb_442f

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 6.9, pKa2 = 10.3.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 4.4 Incorrect pI = 8.6 Correct pI = 12.3 Incorrect MC

33dc_2a8f

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 6.8, pKa2 = 9.9.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 4.7 Incorrect pI = 8.3 Correct pI = 12.0 Incorrect MC

bcc0_9e16

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 3.8, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 2.8 Correct pI = 6.7 Incorrect pI = 11.8 Incorrect MC

669c_a78d

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 5.0, pKa2 = 9.2.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.6 Correct pI = 7.1 Incorrect pI = 11.9 Incorrect MC

a5dc_3b55

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 6.9, pKa2 = 9.0.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 4.9 Incorrect pI = 8.0 Correct pI = 11.3 Incorrect MC

cd6a_5968

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 4.0, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 2.9 Correct pI = 6.8 Incorrect pI = 11.8 Incorrect MC

daed_df66

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 3.7, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 2.8 Correct pI = 6.6 Incorrect pI = 11.9 Incorrect MC

eba7_1876

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 5.9, pKa2 = 9.2.

The isoelectric point (pI) is closest to which value?

pI = 1.3 Incorrect pI = 4.2 Incorrect pI = 7.5 Correct pI = 11.3 Incorrect MC

f275_915c

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 7.7, pKa2 = 10.4.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 5.2 Incorrect pI = 9.1 Correct pI = 12.2 Incorrect MC

af8d_0fa7

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 4.1, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 3.2 Correct pI = 6.5 Incorrect pI = 11.8 Incorrect MC

e4ce_b3ed

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 4.7, pKa2 = 10.5.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.5 Correct pI = 7.9 Incorrect pI = 12.2 Incorrect MC

2f51_0515

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 3.8, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 2.8 Correct pI = 6.9 Incorrect pI = 12.1 Incorrect MC

d96c_8d9e

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 4.5, pKa2 = 9.9.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.3 Correct pI = 7.3 Incorrect pI = 11.8 Incorrect MC

9055_ab84

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 4.1, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 0.6 Incorrect pI = 2.9 Correct pI = 7.4 Incorrect pI = 12.1 Incorrect MC

53f8_c1ab

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 6.4, pKa2 = 10.5.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 4.0 Incorrect pI = 8.4 Correct pI = 12.3 Incorrect MC

f191_567e

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 3.7, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 2.8 Correct pI = 6.6 Incorrect pI = 11.9 Incorrect MC

7ba0_bdb1

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 4.0, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 1.3 Incorrect pI = 3.0 Correct pI = 6.8 Incorrect pI = 11.8 Incorrect MC

9223_1f25

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 6.5, pKa2 = 9.8.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.1 Incorrect pI = 8.2 Correct pI = 11.7 Incorrect MC

ab2d_f407

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 3.8, pKa2 = 10.4.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 2.8 Correct pI = 6.8 Incorrect pI = 12.4 Incorrect MC

ae91_bb77

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 6.3, pKa2 = 9.0.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 4.0 Incorrect pI = 7.7 Correct pI = 11.2 Incorrect MC

65b3_4a63

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 4.2, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 3.0 Correct pI = 7.2 Incorrect pI = 12.1 Incorrect MC

aba8_11a3

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 4.5, pKa2 = 9.3.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.4 Correct pI = 6.7 Incorrect pI = 11.8 Incorrect MC

77af_af7e

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 5.0, pKa2 = 9.2.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.8 Correct pI = 7.3 Incorrect pI = 11.4 Incorrect MC

0973_e732

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 7.5, pKa2 = 9.6.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 4.6 Incorrect pI = 8.6 Correct pI = 11.5 Incorrect MC

8ad3_9722

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 7.1, pKa2 = 9.2.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 4.8 Incorrect pI = 8.1 Correct pI = 11.8 Incorrect MC

33b4_eed9

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 7.4, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 4.6 Incorrect pI = 8.4 Correct pI = 11.8 Incorrect MC

4033_cfca

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 6.0, pKa2 = 9.8.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 4.3 Incorrect pI = 7.9 Correct pI = 12.0 Incorrect MC

ca07_9c43

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 4.7, pKa2 = 9.2.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.4 Correct pI = 7.2 Incorrect pI = 11.3 Incorrect MC

6380_df61

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 5.9, pKa2 = 9.4.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.6 Incorrect pI = 7.7 Correct pI = 11.9 Incorrect MC

dabe_a837

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 7.3, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 0.7 Incorrect pI = 4.4 Incorrect pI = 8.5 Correct pI = 11.8 Incorrect MC

0530_3db6

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 7.8, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 0.6 Incorrect pI = 4.9 Incorrect pI = 8.8 Correct pI = 11.9 Incorrect MC

1d8f_688e

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 4.5, pKa2 = 10.3.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.2 Correct pI = 7.7 Incorrect pI = 12.2 Incorrect MC

09cc_0a29

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 7.1, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 0.6 Incorrect pI = 4.8 Incorrect pI = 8.3 Correct pI = 12.1 Incorrect MC

069c_ccec

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 4.8, pKa2 = 9.8.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.4 Correct pI = 7.5 Incorrect pI = 12.1 Incorrect MC

6e10_f2b9

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 4.4, pKa2 = 9.3.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 3.4 Correct pI = 6.9 Incorrect pI = 11.3 Incorrect MC

ceaa_89ca

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.5, pKaR = 6.3, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.7 Incorrect pI = 7.9 Correct pI = 11.4 Incorrect MC

fb42_8b3f

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 7.5, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 4.7 Incorrect pI = 8.6 Correct pI = 11.8 Incorrect MC

af9c_5481

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 4.8, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 1.5 Incorrect pI = 3.6 Correct pI = 7.7 Incorrect pI = 12.4 Incorrect MC

7e3a_6e36

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 6.9, pKa2 = 9.9.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 4.6 Incorrect pI = 8.4 Correct pI = 12.2 Incorrect MC

9b87_715f

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 4.2, pKa2 = 10.3.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 3.2 Correct pI = 7.3 Incorrect pI = 12.1 Incorrect MC

2a79_2e4a

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 8.0, pKa2 = 10.5.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 5.1 Incorrect pI = 9.2 Correct pI = 12.3 Incorrect MC

fc4a_f859

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 4.0, pKa2 = 10.1.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.2 Correct pI = 7.1 Incorrect pI = 11.9 Incorrect MC

2167_9da7

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 5.8, pKa2 = 9.2.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 4.3 Incorrect pI = 7.5 Correct pI = 11.7 Incorrect MC

1a01_f473

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 5.0, pKa2 = 9.9.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.4 Correct pI = 7.5 Incorrect pI = 11.8 Incorrect MC

ab91_722e

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 8.0, pKa2 = 9.4.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 4.9 Incorrect pI = 8.7 Correct pI = 11.5 Incorrect MC

9ee0_6a3f

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 3.5, pKa2 = 9.4.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 2.9 Correct pI = 6.2 Incorrect pI = 11.4 Incorrect MC

2ed2_6d51

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 4.6, pKa2 = 10.4.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 3.3 Correct pI = 7.4 Incorrect pI = 12.1 Incorrect MC

01c8_8914

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 8.0, pKa2 = 9.8.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.7 Incorrect pI = 8.9 Correct pI = 11.8 Incorrect MC

e1e1_08bd

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 4.8, pKa2 = 10.0.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.5 Correct pI = 7.6 Incorrect pI = 12.1 Incorrect MC

8307_7ad0

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 7.1, pKa2 = 10.0.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 4.7 Incorrect pI = 8.6 Correct pI = 11.7 Incorrect MC

9415_a5c3

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 4.6, pKa2 = 10.3.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.4 Correct pI = 7.7 Incorrect pI = 12.5 Incorrect MC

5e46_8f2d

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 4.8, pKa2 = 10.1.

The isoelectric point (pI) is closest to which value?

pI = 1.3 Incorrect pI = 3.6 Correct pI = 7.3 Incorrect pI = 11.9 Incorrect MC

dbad_59ec

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 5.5, pKa2 = 9.9.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 3.5 Incorrect pI = 7.7 Correct pI = 12.1 Incorrect MC

8489_7c9b

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 6.2, pKa2 = 9.2.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.3 Incorrect pI = 7.7 Correct pI = 11.3 Incorrect MC

7585_f7c3

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 4.1, pKa2 = 9.9.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 3.1 Correct pI = 7.2 Incorrect pI = 12.1 Incorrect MC

53d9_af72

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 7.7, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 5.0 Incorrect pI = 8.6 Correct pI = 11.4 Incorrect MC

d2d1_475c

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 5.0, pKa2 = 9.9.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 3.6 Correct pI = 7.4 Incorrect pI = 11.8 Incorrect MC

463c_402e

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
COOH
CH3
→
State 2
H3N+
COO−
COOH
CH3
→
State 3
H3N+
COO−
COO−
CH3
→
State 4
H2N
COO−
COO−
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 4.9, pKa2 = 9.0.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 3.5 Correct pI = 7.2 Incorrect pI = 11.5 Incorrect MC

ae9a_7092

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 6.8, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 4.2 Incorrect pI = 8.5 Correct pI = 12.3 Incorrect MC

e8eb_3e11

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 4.3, pKa2 = 9.5.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 3.3 Correct pI = 7.1 Incorrect pI = 11.9 Incorrect MC

4e7f_ad01

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
NH3+
CH3
H3N+
→
State 2
COO−
NH3+
CH3
H3N+
→
State 3
COO−
NH2
CH3
H3N+
→
State 4
COO−
NH2
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 6.9, pKa2 = 9.7.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 4.3 Incorrect pI = 8.3 Correct pI = 11.7 Incorrect MC

1cd1_aebc

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.9, pKaR = 7.7, pKa2 = 9.6.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 4.6 Incorrect pI = 8.7 Correct pI = 12.1 Incorrect MC

205a_3ba7

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 6.3, pKa2 = 10.5.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 4.0 Incorrect pI = 8.4 Correct pI = 11.9 Incorrect MC

ad8c_3384

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
COOH
CH3
H3N+
→
State 2
COO−
COOH
CH3
H3N+
→
State 3
COO−
COO−
CH3
H3N+
→
State 4
COO−
COO−
CH3
H2N
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 1.8, pKaR = 3.6, pKa2 = 10.2.

The isoelectric point (pI) is closest to which value?

pI = 1.2 Incorrect pI = 2.7 Correct pI = 6.7 Incorrect pI = 11.9 Incorrect MC

15e5_0cb7

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
COOH
CH3
H3N+
COOH
→
State 2
COOH
CH3
H3N+
COO−
→
State 3
COO−
CH3
H3N+
COO−
→
State 4
COO−
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.0, pKaR = 4.4, pKa2 = 9.4.

The isoelectric point (pI) is closest to which value?

pI = 0.8 Incorrect pI = 3.2 Correct pI = 6.6 Incorrect pI = 11.7 Incorrect MC

f554_c697

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
NH3+
→
State 2
CH3
H3N+
COO−
NH3+
→
State 3
CH3
H3N+
COO−
NH2
→
State 4
CH3
H2N
COO−
NH2
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.4, pKaR = 6.8, pKa2 = 10.4.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 4.6 Incorrect pI = 8.6 Correct pI = 12.5 Incorrect MC

f546_d240

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 3.6, pKa2 = 9.1.

The isoelectric point (pI) is closest to which value?

pI = 1.0 Incorrect pI = 2.9 Correct pI = 6.1 Incorrect pI = 11.7 Incorrect MC

bb6f_de44

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
CH3
H3N+
COOH
COOH
→
State 2
CH3
H3N+
COO−
COOH
→
State 3
CH3
H3N+
COO−
COO−
→
State 4
CH3
H2N
COO−
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.1, pKaR = 3.7, pKa2 = 10.5.

The isoelectric point (pI) is closest to which value?

pI = 0.9 Incorrect pI = 2.9 Correct pI = 7.4 Incorrect pI = 12.6 Incorrect MC

1530_12a6

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
H3N+
COOH
NH3+
CH3
→
State 2
H3N+
COO−
NH3+
CH3
→
State 3
H3N+
COO−
NH2
CH3
→
State 4
H2N
COO−
NH2
CH3
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.3, pKaR = 7.1, pKa2 = 9.9.

The isoelectric point (pI) is closest to which value?

pI = 1.4 Incorrect pI = 4.5 Incorrect pI = 8.5 Correct pI = 11.8 Incorrect MC

8487_5ce3

Isoelectric Point from Titration Curve

Below are four protonation states of a hypothetical molecule, shown in order as the solution is titrated from low pH to high pH.

State 1
NH3+
CH3
H3N+
COOH
→
State 2
NH3+
CH3
H3N+
COO−
→
State 3
NH2
CH3
H3N+
COO−
→
State 4
NH2
CH3
H2N
COO−
12
10
8
6
4
2
           pKa2
           
            
            
           pKaR
           
            
            
           pKa1
           
            
            
0123 
OH− (equivalents) 

Given pKa values: pKa1 = 2.2, pKaR = 7.0, pKa2 = 10.3.

The isoelectric point (pI) is closest to which value?

pI = 1.1 Incorrect pI = 4.4 Incorrect pI = 8.7 Correct pI = 12.0 Incorrect