Question

An insecticide has the following percentage composition by mass: 47.5% C, 2.54% H, and 50.0% Cl. Determine its empirical formula and molecular formulae. Molar mass of the substance is 354.5 g mol^-1

Answer 1

The empirical formula is C₁₄H₉C₁₅ . 

Calculation of Molecular formula: 

The empirical formula mass (C₁₄H₉C₁₅ ) = (14 X 12) + (9 X 1) + (5 X 35.5)

n = (Molecular mass) / (Empirical formula mass) 

= 354.5 / 354.5

= 1

Empirical formula mass 354.5 

Molecular formula = (Empirical formu1a)_n 

= (C₁₄H₉Cl₅)₁ 

∴ Molecular formula = C₁₄H₉Cl₅