Sulfur trioxide is prepared by the following reactions:
$S_{8(s)} + 8O_{2(g)} \to 8SO_{2(g)}$
$2SO_{2(g)} + O_{2(g)} \to 2SO_{3(g)}$
How many grams of $SO_3$ are obtained from $1 \ mol$ of $S_8$?

The molecular weight of a gas is $45$. Its density at $STP$ is

$A$ given initial mass of $KClO_3$ on $50\%$ decomposition produces $67.2 \ L$ of oxygen gas at $0 \ ^\circ C$ and $1 \ atm$. The other product of decomposition is $KCl$. The initial mass of $KClO_3$ (in $g$) taken is:

$H_2$ evolved at $STP$ on complete reaction of $27 \ g$ of Aluminium with excess of aqueous $NaOH$ would be $............ \ L$

For the combustion reaction of $1 \, mol$ of a hydrocarbon $C_xH_y$,the coefficients of $O_2$,$CO_2$,and $H_2O$ involved are respectively:

If isobutane and $n$-butane are present in a gas,then how much oxygen should be required for the complete combustion of $5 \ kg$ of this gas?