The given empirical form aula of compound is CH20
The given molar mass of a compound of 120g/ml
Molar mass of empirical formula
CH20=30g/ml
n= molar mass/ molar mass of empirical formula substitute as follows: n= 120g/ml/30g/ml
n= 4 so, 4 x CH20= C4H8O4
Therefore, the molecular formula of a compound is determined to be C4H8O4
