Question

a gaseous hydrocarbon contains 80% of carbon by weight if one litre of hydrocarbon weighs 2.68 gram find the molecular formula of the hydrocarbon​

Answer 1

Answer:

Carbon : Hydrogen mole ratio =85.7/12

= 7:14 = 1:2

Empirical formula = C,H2n : empirical

formula wt = 14

Given 1 litre at NTP weighs 1.26 g

Therefore 22.4 litres will weigh 22.4/1.26 = 28g

n=28/14 = 2

so the formula is C2H4