Question

2. The Food and Drug Administration (FDA) mandates that all vinegar sold in the United States must have a minimum concentration of 4% acetic acid by mass. Calculate the minimum molarity of acetic acid in vinegar according to this standard. Assume the density of vinegar is the same as for water.

Answer 1

Answer:

The minimum molarity of acetic acid in vinegar according to given standards is 0.6660 mol/L.

Explanation:

4% acetic acid by mass means that 4 gram of acetic acid in 100 g solution.

Given that density of the vinegar is same is that of water =  1 g/mL

Mass of the vinegar solution = 100 g

Volume of the vinegar solution = V

$Density=\frac{Mass}{Volume}$

$1 g/mL=\frac{100 g}{V}$

V = 100 mL = 0.1 L

Moles of acetic acid =$\frac{4 g}{60.052 g/mol}=0.0666 mol$

$Molarity=\frac{\text{Moles of solute}}{\text{Volume of solution(L)}}$

$M=\frac{0.0666 mol}{0.1 L}=0.6660 mol/L$

The minimum molarity of acetic acid in vinegar according to given standards is 0.6660 mol/L.