Which of the following has the highest chlorine content by mass?

The molecular formula of sulphur is

$A$ hydrocarbon contains $80\% \ C$. The vapour density of the compound is $30$. The molecular formula of the compound is :-

$A$ welding fuel gas contains carbon and hydrogen only. Burning a small sample of it in oxygen gives $3.38 \, g$ of carbon dioxide,$0.690 \, g$ of water,and no other products. $A$ volume of $10.0 \, L$ (measured at $STP$) of this welding gas is found to weigh $11.6 \, g$. Calculate:
$(i)$ empirical formula,
$(ii)$ molar mass of the gas,and
$(iii)$ molecular formula.

On complete combustion,$1.0 \ g$ of an organic compound $(X)$ gave $1.46 \ g$ of $CO_2$ and $0.567 \ g$ of $H_2O$. The empirical formula mass of compound $(X)$ is $.......... \ g \ mol^{-1}$. (Given molar mass in $g \ mol^{-1}: C: 12, H: 1, O: 16$)

Two elements,$X$ and $Y$,have atomic numbers $33$ and $17$,respectively. The molecular formula of a stable compound formed between them is