Chemistry – Physical chemistry | e-Consult

Solution:

1. Calculate the molar mass of the empirical formula:

   Molar mass of C₂H₄O₂ = (2 x 12.01) + (4 x 1.01) + (2 x 16.00) = 24.02 + 4.04 + 32.00 = 60.06 g/mol

2. Calculate the ratio of the molar mass of the compound to the molar mass of the empirical formula:

   Ratio = 120 g/mol / 60.06 g/mol = 1.996 ≈ 2

3. Multiply the subscripts in the empirical formula by the ratio to obtain the molecular formula:

   Molecular formula = C_2xH_4xO_2x = C_2*2H_4*2O_2*2 = C₄H₈O₄