At a given temperature,the rate of diffusion of methane is twice that of gas $X$. The molecular weight of $X$ is ...... .

$A$ vessel of volume $V \ L$ contains an ideal gas at $T \ K$. The vessel is partitioned into two equal parts. The volume (in $L$) and temperature (in $K$) in each part is respectively

$50 \ mL$ of hydrogen diffuses out through a small hole from a vessel in $20 \ min$. The time needed for $40 \ mL$ of oxygen to diffuse out is ............. $min$.

Which of the following is not considered in the calculation of the rate of diffusion according to Graham's Law?

$3.2 \ g$ of oxygen is diffused in $10 \ min$. Under similar conditions,$2.8 \ g$ of nitrogen will diffuse in .............. $min$.

To which of the following gaseous mixtures is Dalton's law of partial pressures not applicable?