Acetic acid has a molar mass of 60.05 g/mol and consists of 40.00% C, 6.714% H, and 53.29% O. What is the molecular formula of acetic acid?

Question

Quizplus · Accepted Answer

1. Calculate the number of moles for each element: - Carbon (C) : 40.00 g/mol / 12.01 g/mol = 3.332 moles - Hydrogen (H) : 6.714 g/mol / 1.01 g/mol = 6.65 moles - Oxygen (O) : 53.29 g/mol / 16.00 g/mol = 3.33 moles 2. Divide each number of moles by the smallest number of moles to get the mole ratio: - C : 3.332 / 3.33 = 1 - H : 6.65 / 3.33 ≈ 2 - O : 3.33 / 3.33 = 1 3. The empirical formula is thus CH2O. 4. Calculate the empirical formula mass: - ( 1 x 12.01 g/mol ) + ( 2 x 1.01 g/mol ) + ( 1 x 16.00 g/mol ) = 30.03 g/mol 5. Divide the molar mass by the empirical formula mass to get the integer factor: - 60.05 g/mol / 30.03 g/mol = 2 6. Multiply each subscript in the empirical formula by the integer factor to get the molecular formula: - C2H4O2 Therefore, the molecular formula of acetic acid is C₂H₄O₂.

Acetic Acid Has a Molar Mass of 60