$64 \, g$ of an organic compound contains $24 \, g$ of carbon,$8 \, g$ of hydrogen,and the rest oxygen. The empirical formula of the compound is

$0.30 \ g$ of an organic compound containing $C$,$H$ and $O$ on combustion yields $0.44 \ g \ CO_2$ and $0.18 \ g \ H_2O$. If $1 \ mol$ of the compound weighs $60 \ g$,then the molecular formula of the compound is:

The empirical formula of a carbohydrate is $CH_2O$. If $0.1 \, \text{mol}$ of this carbohydrate contains $1 \, g$ of hydrogen,what is its molecular formula?

The value of $n$ in the molecular formula $Be_n Al_2 Si_6 O_{18}$ is

Calculate the mass percent of different elements present in sodium sulphate $(Na_{2}SO_{4})$.

$A$ sample of calcium carbonate $(CaCO_3)$ has the following percentage composition: $Ca = 40\%$; $C = 12\%$; $O = 48\%$. If the law of constant proportions is true,then the weight of calcium in $4 \, g$ of a sample of calcium carbonate obtained from another source will be $... \, g$.