Question

An organic fruit smelling compound on analysis has the following composition by mass: C = 54.54%, H = 9.09%, O = 36.36%. Find out the molecular formula of the compound. The vapour density of the compound was found to be 44.

Answer 1

∴ The empirical formula is C₂H₄O

Theempirical formula mass (C₂H₄O) = (12 x 2)+(1 x 4)+(16 x 1) = 44 

Molecular mass = 2 x (Vapour density) 

= 2 x 44 

= 88 

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

= 88/44 

= 2 

Molecular formula = (Empirical formula)_n 

= (C₂H₄O)₂ 

∴ Molecular formula = C₂H₄O₂