Question

Two elements${\mathrm{XY}}_2$ X atomic weight 75 and Y atomic weight 16 combine to give compound having 75.8% of X. The formula of the compound is

Answer 1

Elements	% composition	Atomic ratio	Simplest ratio
X	75.8%	75.875=1.011	1.0111.011=1
Y	24.2%	24.216=1.513	1.5131.011=1.5or2

So from this, we found that the empirical formula of the compound is XY2

The molecular formula of the compound = ${\mathrm{XY}}_2$