Suppose the chemical formula of the compound be
CxHyOz chemical reaction related to combustion of the compound.
since, 2 molecules of
CO2 have 2 atoms of carbon and these carbon must have come from the compound.
Hence, the value of
x is
2. Again, 2 molecules of steam contain 4 atoms of hydrogen and they have come from the compound. Hence, the value of
y will be
4. Again, total oxygen atoms in the product side
=6 But 4 oxygen atoms must have come from the oxygen molecules. Hence 2 oxygen atoms definitely come from the compound. Hence, the value of
z=2. So, the molecular formula of the compound is
C2H4O2.