Question

A certain hydrocarbon A was found to contain 85.7 percent carbon and 14.3 percent hydrogen. This compound consumes 1 molar equivalent of hydrogen to give a saturated hydrocarbon B. 1.00 g of hydrocarbon A just decolourised 38.05 g of a 5 percent solution (by weight) of Br₂ in CCl₄. Compound, A on oxidation with concentrated KMnO₄, gave compound C (molecular formula, C₄H₈O) and acetic acid. Compound C could easily be prepared by the action of acidic aqueous mercuric sulphate on 2-butyne. Determine the molecular formula of A and deduce the structure of A, B and C.

Answer 1

 (i) For empirical formula :

.'. Empirical formula = CH₂

(ii) 1 g of hydrocarbon uses 38.05 g of 5% solution of Br₂ in CCl₄, since it is alkene, one mole A uses 1 mole of Br₂.

(iii) Compound C is also prepared by the action of 

(iv) Since A(C₆H₁₂), on oxidation gives C and CH₃COOH, hence, A is