Question

How many grams of acetic acid are present in 250.0mL of vinegar, assuming the 5% v/v indicated on the label is accurate?

Answer 1

There are 13 g of acetic acid.

Explanation:

Step 1. Calculate the volume of acetic acid

`"Volume" = 250.0 color(red)(cancel(color(black)("mL vinegar"))) × "5 mL acetic acid"/(100 color(red)(cancel(color(black)("mL vinegar")))) = "12 g acetic acid"`

Step 2. Calculate the mass of acetic acid

The density of acetic acid is 1.05 g/mL.

`"Mass of acetic acid" = 12 color(red)(cancel(color(black)("mL acetic acid"))) × "1.05 g acetic acid"/(1 color(red)(cancel(color(black)("mL acetic acid")))) = "13 g acetic acid"`

Note: The answer can have only one significant figure because that is all you gave for the percent concentration. However, I calculated the result to two significant figures.