An oxide of iron,which contains $69.9 \%$ iron and $30.1 \%$ dioxygen by mass,has the empirical formula:

$0.102 \ g$ of an organic compound $X$ was oxidised with fuming nitric acid. The resulting solution,after reaction with excess of aqueous $BaCl_2$,produced $0.233 \ g$ of $BaSO_4$ as a precipitate. Compound $X$ is likely to be: [Given: Atomic wt. of $Ba = 137$]

$A$ compound contains $10^{-2} \%$ of phosphorus. If the atomic mass of phosphorus is $31$,the molecular mass of the compound having one phosphorus atom per molecule is :-

In $CH_3CH_2Br$,the percentage of $Br$ is:

Which of the following has the highest percentage of chlorine?

An organic compound gave the following results: $C = 53.3\%$,$H = 15.6\%$,$N = 31.1\%$. The molecular weight of the compound is $45$. What is the molecular formula of the compound?