A compound with empirical formula XY2, has the vapour density equal to its empirical formula weight, its molecular formula is
Step 1: Given
The empirical formula for a compound of X and Y is
Step 2: Basis of calculation
As we know a molecule has the same vapour density as its empirical formula weight.
Vapour density is the measurement of pressure applied by gaseous vapours.
The molecular weight is equal to the density of the vapour.
Step 3: Deriving the molecular formula
As a result, the molecular weight is twice that of the empirical formula.
is the molecular formula.
Hence the molecular formula is .