$A$ substance contains $38.8\% \, C$,$16\% \, H$,and $45.2\% \, N$. What is the empirical formula of the substance?

Urea is a better fertilizer than ammonium sulphate because

$60 \ g$ of a compound on analysis gave $C = 24 \ g$,$H = 4 \ g$ and $O = 32 \ g$. Its empirical formula is

The empirical formula of a compound is $CH_2$. If the molar mass of the compound is $42 \ g/mol$,what is its molecular formula?

An organic compound with a molecular weight of $60$ contains $C = 20\%$,$H = 6.67\%$,and $N = 46.67\%$,with the remainder being oxygen. Upon heating,the solid residue gives a violet color with alkaline copper sulfate solution. Identify the compound.

An organic compound containing $C$ and $H$ has $92.3 \%$ of carbon. Its empirical formula is: