An organic compound has an empirical formula of $CH_2O$ and a molecular mass of $90$. What is its molecular formula? $(C = 12, H = 1, O = 16)$

An organic compound has been found to possess the empirical formula $CH_2O$ and molecular weight $90$. The molecular formula of it is $(C = 12, H = 1, O = 16)$.

Determine the empirical formula of Kevlar,used in making bulletproof vests,which contains $70.6 \% \, C, \, 4.2 \% \, H, \, 11.8 \% \, N$ and $13.4 \% \, O$.

Determine the molecular formula of an oxide of iron in which the mass per cent of iron and oxygen are $69.9$ and $30.1$ respectively. Given that the molar mass of the oxide is $159.69 \, g \, mol^{-1}$.

On complete combustion,$1.4 \, g$ of a hydrocarbon gave $1.8 \, g$ of water. The empirical formula of the hydrocarbon is:

On complete combustion of $0.492 \ g$ of an organic compound containing $C, H$ and $O$,$0.7938 \ g$ of $CO_2$ and $0.4428 \ g$ of $H_2O$ were produced. The percentage composition of oxygen in the compound is $........$