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

$A$ gaseous mixture was prepared by taking equal moles of $CO$ and $N_2$. If the total pressure of the mixture was found to be $1 \ atm$,the partial pressure of the nitrogen $(N_2)$ in the mixture is ............ $atm$.

At a certain temperature, the time required for the complete diffusion of $200 \ mL$ of $H_2$ gas is $30 \ min$. The time required for the complete diffusion of $50 \ mL$ of $O_2$ gas at the same temperature will be: (in $min$)

Normal boiling point of water is $373 \ K$ (at $760 \ mm$). Vapour pressure of water at $298 \ K$ is $23 \ mm$. If the enthalpy of evaporation is $40.656 \ kJ/mole$,the boiling point of water at $23 \ mm$ pressure will be ............. $K$.

The rate of diffusion of $SO_3$,$CO_2$,$PCl_3$ and $SO_2$ gases are in the following order:

$A$ closed vessel contains an equal number of molecules of $N_2$ and $O_2$ at a pressure of $650 \ mm$. If $N_2$ is completely removed,what will be the pressure in the vessel?