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?

What is the percentage composition of $C$ in methanoic anhydride?

Arrange the following compounds in the increasing order of percentage of chlorine by weight:
$I.$ $DDT$ $(C_{14}H_9Cl_5)$
$II.$ Gammaxene $(C_6H_6Cl_6)$
$III.$ Carbon tetrachloride $(CCl_4)$
$IV.$ Chlorobenzene $(C_6H_5Cl)$

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

Carbon percentage is maximum in

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.