The sulphate of a metal $M$ contains $9.87\%$ of $M$. This sulphate is isomorphous with $ZnSO_4 \cdot 7H_2O$. The atomic weight of $M$ is (in $.3$)

The complete combustion of $0.492 \, g$ of an organic compound containing $'C'$,$'H'$,and $'O'$ gives $0.793 \, g$ of $CO_{2}$ and $0.442 \, g$ of $H_{2}O$. The percentage of oxygen composition in the organic compound is .... (nearest integer)

$0.24 \ g$ of an organic compound gave $0.22 \ g$ $CO_2$ on complete combustion. If it contains $1.66 \%$ hydrogen,then the percentage of $C$ and $O$ will be

In an organic compound,the weight ratio of $C$,$H$,and $N$ atoms is $9 : 1 : 3.5$. If the molecular weight of the compound is $108$,what is its molecular formula?

What is the mass percent of oxygen in ethanol $(C_2H_5OH)$ (in $\%$)?

On complete combustion,$0.492 \ g$ of an organic compound gave $0.792 \ g$ of $CO_2$. The $\%$ of carbon in the organic compound is $..................$ (Nearest integer)