Question

An organic compound contains 49.3% carbon, 6.84% hydrogen and its vapour density is 73. Molecular formula of compound is

(a) C₆H₁₀O₄

(b) C₄H₁₀O₂

(c) C₃H₅O₂

(d) C₃H₁₀O₂

Answer 1

Correct option is (a) C₆H₁₀O₄

Element	%	Molar ratio	Relative ratio
C	49.30	4.1	1.50 x 4 = 6.0
H	6.84	6.84	2.50 x 4 = 10.0
O	43.86	2.74	1.00 x 4 = 4.0

\(\therefore \) Empirical formula = C₆H₁₀O₄

Empirical formula wt = 72 + 10 + 64 = 146

Mol. wt. 2 X V.D. = 2 x 73 = 146 

\(\therefore \) Molecular formula (C₆H₁₀O₄)₁ = C₆H₁₀O₄