Question

Carbohydrate containing 40% carbon, 6.73% hydrogen and 53.3% oxygen.

The molecular mass of compound is 180. Determine its molecular formula.

Answer 1

∴ Empirical formula = CH₂O.

Molecular mass of compound =180

Empirical mass = CH₂O = 12 + 2 × 1.008 + 16 = 30

n = M.M/E.M = 180/30 = 6

Molecular formula = C₆H₁₂O₆ = Glucose