If $N_2, O_2, H_2$,and $He$ gases are filled separately in four car tubes at the same pressure,which gas will diffuse first?

$A$ sample of air contains $N_2$ and $O_2$ saturated with water vapor,with a total pressure of $640 \ torr$. If the water vapor pressure is $40 \ torr$ and the molar ratio of $N_2$ to $O_2$ is $3 : 1$,what is the partial pressure of $N_2$ in the sample in $torr$?

The pressure under which liquid and vapour can coexist at equilibrium is called the

Deep sea divers use a mixture of which gases for respiration?

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

The behaviour of matter in different states is governed by various physical laws. According to you,what are the factors that determine the state of matter?