Answer
20. mL of that solution contains 2.0 mL of formic acid.
Work Step by Step
1. Identify the conversion factors:
- Since the formic acid solution is 10.0% (v/v):
10.0 mL (Solute) = 100 mL (Solution)
So: $\frac{10.0 \space mL \space (Solute)}{100 \space mL \space (Solution)}$ and $\frac{100 \space mL \space (Solution)}{10.0 \space mL \space (Solute)}$
2. Calculate the volume of solution that contains 2.0 mL of formic acid:
$2.0 \space mL \space (Solute) \times \frac{100 \space mL \space (Solution)}{10.0 \space mL \space (Solute)} = 20. \space mL \space (Solution)$