What is the volume (in litres) of oxygen at STP required for complete combustion of $32 \mathrm{~g}$ of…
What is the volume (in litres) of oxygen at STP required for complete combustion of $32 \mathrm{~g}$ of $\mathrm{CH}_4$ ?
(Molecular weight of $\mathrm{CH}_4$ is 16 )
$44.8$
$89.6$
$22.4$
$179.2$
Solution
$\underset{16 \mathrm{~g}}{\mathrm{CH}_4}+\underset{2 \times 22.4 \mathrm{~L}}{2 \mathrm{O}_2} \longrightarrow \mathrm{CO}_2+2 \mathrm{H}_2 \mathrm{O}$
Volume of required for $16 \mathrm{~g}_4$ is $=2 \times 22.4 \mathrm{~L}$ Volume of $\mathrm{O}_2$ required for $32 \mathrm{~g} \mathrm{CH}_4$ is
$=\frac{2 \times 22.4}{16} \times 32=89.6 \mathrm{~L}$