Equal masses of ${\mathrm{H}}_2,{\mathrm{O}}_2$ and methane have been taken in a container of volurne (V) at temperature 27°C in identical conditions. The ratio of the volumes of gases ${\mathrm{H}}_2:{\mathrm{O}}_2:{\mathrm{CH}}_4$ would be

Equal masses of ${\mathrm{H}}_2,{\mathrm{O}}_2\text{ and }{\mathrm{CH}}_4$ are taken in volume (V )of container, volume of gas $\propto$ number of moles (Avogadro's law)
Volume of ${\mathrm{H}}_2$ : Volume of ${\mathrm{O}}_2$ : Volume of ${\mathrm{CH}}_4$

$=\frac{\mathrm{w}}{2}:\frac{\mathrm{w}}{32}:\frac{\mathrm{w}}{16}\left({\mathrm{M}}_{{\mathrm{H}}_2}=2,{\mathrm{M}}_{{\mathrm{O}}_2}=32,{\mathrm{M}}_{{\mathrm{CH}}_4}=16\right)$

= 16 : 1 : 2