Chemistry - Mole Concept Question with Solution | TestHub

The balanced chemical equation for the combustion of methane is:

$\mathrm{C}{\mathrm{H}}_4(\mathrm{g})+2{\mathrm{O}}_2(\mathrm{g})\to \mathrm{C}{\mathrm{O}}_2(\mathrm{g})+2{\mathrm{H}}_2\mathrm{O}(\mathrm{l})$

From the stoichiometry of the reaction, $1$ mole of methane requires $2$ moles of oxygen for complete combustion.

Therefore, $0.25$ mole of methane requires $2\times 0.25=0.50$ mole of oxygen.

At S.T.P., the volume occupied by $1$ mole of a gas is $22.4\mathrm{d}{\mathrm{m}}^3$.

Volume of oxygen required $=0.50\times 22.4\mathrm{d}{\mathrm{m}}^3=11.2\mathrm{d}{\mathrm{m}}^3$.

Answer: $11.2{\mathrm{dm}}^3$