In a 1:2 dilution, what fraction of the final solution is solvent?

In a 1:2 dilution, what fraction of the final solution is solvent?

• A. 1/3
• B. 2/3
• C. 1/2
• D. 3/4

Answer: (D)

In a 1:2 dilution, there are 3 parts in the final mixture: 1 part solute and 2 parts solvent. The solvent makes up 2 of those 3 parts, so the fraction of the final solution that is solvent is 2/3. For example, mixing 1 mL of stock with 2 mL of solvent yields 3 mL total, 2 mL of which is solvent, i.e., two-thirds of the final volume.

In a 1:2 dilution, there are 3 parts in the final mixture: 1 part solute and 2 parts solvent. The solvent makes up 2 of those 3 parts, so the fraction of the final solution that is solvent is 2/3. For example, mixing 1 mL of stock with 2 mL of solvent yields 3 mL total, 2 mL of which is solvent, i.e., two-thirds of the final volume.