Question

The empirical formula of a compound is $C{H}_{2}O$. $0.0835$ moles of compound contains $1.0$ g of hydrogen. Molecular formula of the compound is :

• A. $C_6{H}_{12}{O}_6$
• B. $C_5{H}_{10}{O}_5$
• C. $C_4{H}_8{O}_8$
• D. $C_3{H}_6{O}_3$

Answer 1

The correct option is A $C_6{H}_{12}{O}_6$

Since, the empirical formula of the compound is $C{H}_{2}O$, its molecular formula can be written as,

$\Rightarrow n\left(C{H}_{2}O\right)=C_n{H}_{2n}{O}_n$

It is given that $0.0835$ moles of the compound contains $1g$ of $H$, it means $\left(2n\right)\times \left(0.0835\right)$ moles of $H$ in the compound contains $1g$ of $H$.

Therefore,

$2n\times \left(0.0835\right)=1$

$2n=11.97\approx 12$

$n=6$

So, the molecular formula of $C{H}_{2}O$ is $C_6{H}_{12}{O}_6$.