Acetic acid is the active ingredient in vinegar. It consists of 40.00% C, 6.714% H, and 53.29% O. What is the empirical formula of acetic acid?

Question

Quizplus · Accepted Answer

To determine the empirical formula, we need to convert the percentage of each element to moles by assuming a 100 g sample.

- 40.00 g C / 12.01 g/mol = 3.33 mol C
- 6.714 g H / 1.01 g/mol = 6.64 mol H
- 53.29 g O / 16.00 g/mol = 3.33 mol O

Next, we divide each mole value by the smallest mole value to get the ratio of atoms. In this case, the smallest mole value is 3.33, so:

- C: 3.33 / 3.33 = 1
- H: 6.64 / 3.33 = 1.99 ≈ 2
- O: 3.33 / 3.33 = 1

Therefore, the empirical formula is CH2O, which corresponds to choice C.

Acetic Acid Is the Active Ingredient in Vinegar