The percentage composition of an organic compound is as follows: $C = 10.06\%$,$H = 0.84\%$,$Cl = 89.10\%$. Which of the following corresponds to its molecular formula if the vapour density is $60.0$?

An organic compound has the percentage of $C$ and $H$ in the ratio $6 : 1$ and the percentage of $C$ and $O$ in the ratio $3 : 4$. The compound is:

How many grams of oxygen are present in $32.2 \ g$ of $Na_2SO_4 \cdot 10H_2O$ (in $g$)?

On analysis,a saturated hydrocarbon is found to contain $83.70\%$ carbon and $16.30\%$ hydrogen. The empirical formula will be (at. wt. of $C=12$, at. wt. of $H=1$).

$A$ 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 $10.0 \ L$ of this welding gas (measured at $STP$) is found to weigh $11.6 \ g$. Calculate: $(i)$ Empirical formula,$(ii)$ Molar mass of the gas,$(iii)$ Molecular formula.

The percentage composition of carbon by mole in methane is ........... $ \% $