g Acetic acid is diluted with water to make a solution of vinegar. You have a sample of vinegar that contains 16.7 g of acetic acid. Determine the number of moles of acetic acid in the vinegar sample.

0.278 mol

Explanation:

Step 1: Given and required data

Mass of acetic acid (m): 16.7 g

Chemical formula of acetic acid: CH₃COOH (C₂H₄O₂)

Step 2: Calculate the molar mass (M) of acetic acid

We will use the following expression.

M(C₂H₄O₂) = 2 × M(C) + 4 × M(H) + 2 × M(O)

M(C₂H₄O₂) = 2 × 12.01 g/mol + 4 × 1.01 g/mol + 2 × 16.00 g/mol = 60.06 g/mol

Step 3: Calculate the number of moles (n) of acetic acid

We will use the following expression.

n = m/M

n = 16.7 g/(60.06 g/mol) = 0.278 mol