An organic compound has $C = 60\%$,$H = 13.3\%$ and $O = 26.7\%$. Its empirical formula will be

$A$ pure compound contains $2.4 \ g$ of $C$,$1.2 \times 10^{23}$ atoms of $H$,and $0.2 \ mol$ of oxygen atoms. Its empirical formula is

How many grams of oxygen are present in $32.2 \ g$ of $Na_2SO_4 \cdot 10H_2O$ (in $g$)?

Determine the empirical formula of an oxide of iron which has $69.9 \%$ iron and $30.1 \%$ dioxygen by mass.

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

An organic compound is estimated through the Dumas method and is found to evolve $6$ moles of $CO_2$,$4$ moles of $H_2O$,and $1$ mole of nitrogen gas. The formula of the compound is