Q45 / 200 · NEET 2021 · Chemistry

An organic compound contains $80 %$ (by wt.) carbon and remaining percentage of hydrogen. The right option for the empirical formula of this compound is: [Atomic wt. of $C$ is $12$ and of $H$ is $1$ ]

Solution

$%$ by weight $\begin{array}{l} C & H \\ 80 & 20 \end{array}$

$%$ by moles $\begin{matrix} \frac{80}{12} & \frac{20}{1} \\ 6.67 & 20 \end{matrix}$

Simplest ratio $\begin{matrix} \frac{6.67}{6.67} & \frac{20}{6.67} \\ 1 & 3 \end{matrix}$

Hence, the empirical formula of this compound is ${CH}_{3} .$

Hence, the correct answer is option: 'C'.