Two gases $A$ and $B$ having the same volume diffuse through a porous partition in $20$ and $10$ seconds respectively. The molecular mass of $A$ is $49 \ u$. The molecular mass of $B$ will be .............. $u$.

$A$ hydrocarbon diffuses $3\sqrt{3}$ times slower than hydrogen gas. Identify the hydrocarbon.

Which one of the following statements is not correct about the three states of matter,i.e.,solid,liquid,and gaseous?

$A$ mixture of $N_2$ and $Ar$ gases in a cylinder contains $7 \ g$ of $N_2$ and $8 \ g$ of $Ar$. If the total pressure of the mixture of gases in the cylinder is $27 \ bar$,the partial pressure of $N_2$ is $......... \ bar$.
[Use atomic masses (in $g \ mol^{-1}$) : $N=14, Ar=40$]

Which of the following is true about the gaseous state?

Arrange the states of matter (solid,liquid,and gas) in increasing order of their energy.