$4 \ g$ of a hydrocarbon on complete combustion gave $12.571 \ g$ of $CO_2$ and $5.143 \ g$ of water. What is the empirical formula of the hydrocarbon?

Find the empirical formula of an organic compound if it contains $18.6 \% C$,$1.55 \% H$,and $55.04 \% Cl$. (Atomic masses: $C=12$,$H=1$,$Cl=35.5$,$O=16$)

$0.5 \ g$ 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 $g \ mol^{-1}$: $C: 12, H: 1, O: 16$]

An oxide of copper which is red in colour has the formula

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

An organic compound on analysis gives the following composition: $C = 54.5\%, O = 36.4\%, H = 9.1\%$. The empirical formula of the compound is ..