$A$ gaseous mixture contains $65\%$ $N_2$,$15\%$ $O_2$,and $20\%$ $CO_2$ by volume at a total pressure of $760 \, mm \, Hg$. Calculate the partial pressure of each gas in $mm \, Hg$.

What is the density of water vapour at the boiling point of water?

At $T \ K$,equal weights of $H_2, D_2$,and $T_2$ are present in a closed vessel. The pressure exerted by this gaseous mixture is $P \ atm$. The ratio of partial pressures of $T_2, D_2$,and $H_2$ is approximately. ($H, D$ and $T$ are isotopes of hydrogen).

$A$ vessel contains equal masses of hydrogen,helium,and methane. The total pressure of the mixture is $1300 \ torr$. What is the partial pressure of hydrogen gas in $torr$?

In water saturated air,the mole fraction of water vapour is $0.02$. If the total pressure of the saturated air is $1.2 \; atm$,the partial pressure of dry air is .....$atm$.

$A$ sample of $N_2$ gas at $0.8 \, atm$ pressure takes $38 \, s$ to effuse through a pinhole. $A$ sample of $1 \, mol$ of an unknown gas '$X$' at $1.6 \, atm$ pressure takes $57 \, s$ to effuse through the same pinhole. The molar mass of gas '$X$' in $g/mol$ is .............