Question

Complete combustion of $750\text{g}$ of an organic compound provides $420\text{g}$ of $C{O}_2$ and $210\text{g}$ of $H_{2}O$. The percentage composition of carbon and hydrogen in organic compound is $15.3$ and respectively. (Round off to the nearest integer).

Answer 1

This can be calculated using Liebig's method.
$\therefore$ percentage of $H-$ element $=\frac{2}{18}\times \frac{\text{mass of}{H}_{2}O}{\text{Mass of compound}}\times 100=\frac{2}{18}\times \frac{210}{750}\times 100=3.11\simeq 3$