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2: Solutions

Solution preparation using mass concentration, molarity, and volume ratios.

Calculating Mass for a Target Concentration

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glucose
Volume 125.0 mL
Concentration 8.0 mg/mL
Molecular weight 180.16 g/mol
State Solid powder at room temperature

How many milligrams (mg) of glucose would you need to make 125.0 mL of a 8.0 mg/mL glucose solution?
Note: answers need to be within 1% of the correct number to be correct.

 

Calculating Mass for Weight/Volume Solutions

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Glucose
Volume 40 mL
Concentration 20% (w/v)
Molecular weight 180.16 g/mol
State Solid powder at room temperature

How many grams (g) of glucose (Glucose) you would need to make 40 mL of a 20% (w/v) Glucose solution?
Note: answers need to be within 12% of the correct number to be correct.

 

Calculating Mass for Solutions Using Molarity and Molecular Weight

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sucrose
Volume 320 mL
Concentration 2 mM
Molecular weight 342.30 g/mol
State Solid powder at room temperature

How many milligrams (mg) of sucrose would you need to make 320 mL of a 2 mM sucrose solution?
Note: answers need to be within 1% of the correct number to be correct.

 

Calculating Solute Volume for Percent Volume/Volume Solutions

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acetone
Volume 350 mL
Concentration 4% (v/v)
Molecular weight 58.08 g/mol
State Liquid at room temperature

How many milliliters (mL) of acetone you would need to make 350 mL of a 4% (v/v) acetone solution?
Note: answers need to be within 7% of the correct number to be correct.

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