Question 9.10: How many milliliters of methyl alcohol are needed to prepare...

Fundamentals of General, Organic, and Biological Chemistry

How many milliliters of methyl alcohol are needed to prepare 75 mL of a 5.0% (v/v) solution?
ANALYSIS We are given a solution volume (75 mL) and a concentration [5.0% (v/v), meaning 5.0 mL solute/100 mL solution]. The concentration acts as a conversion factor for finding the amount of methyl alcohol needed.
BALLPARK ESTIMATE A 5% (v/v) solution contains 5 mL of solute in 100 mL of solution, so the amount of solute in 75 mL of solution must be about threefourths of 5 mL, which means between 3 and 4 mL.

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