An organic compound contains carbon,hydrogen,and oxygen. Its elemental analysis gave $C = 38.71 \%$ and $H = 9.67 \%$. The empirical formula of the compound would be:

If $1.24 \ g$ of $P$ is present in a $2.2 \ g$ sample of a compound,identify the empirical formula of the compound (Atomic mass of $P = 31 \ g/mol$,$S = 32 \ g/mol$).

The molecular formula of potash alum is

$0.5 \ g$ of an organic compound on combustion gave $1.46 \ g$ of $CO_2$ and $0.9 \ g$ of $H_2O$. The percentage of carbon in the compound is $...........$ ($NEAREST$ $INTEGER$). [$GIVEN$: Molar mass in $g \ mol^{-1}$: $C: 12, H: 1, O: 16$]

The formula for calcium chlorite is

Number of hydrogen atoms per molecule of a hydrocarbon $A$ having $85.8 \%$ carbon is $...............$. (Given : Molar mass of $A = 84 \ g \ mol^{-1}$ )