Which of the following property of a small drop of mercury can be used to explain the spherical shape of mercury droplets?

$A$ container consists of a mixture of $28 \ g \ N_2$,$8 \ g \ He$,and $40 \ g \ Ne$ at $25^{\circ} C$. If the total pressure exerted by the gaseous mixture is $20 \ bar$,what is the partial pressure exerted by $N_2$ (in $bar$)?

Provide the mathematical expression for Dalton's law of partial pressure.

$3.2 \, g$ of oxygen gas diffuses in $10 \, minute$. Under similar conditions,$2.8 \, g$ of nitrogen gas will diffuse in ............ $minute$.

Which has higher density: dry air or moist air? Why?

$A$ container contains $5 \ mol$ of $A$ and $10 \ mol$ of $B$. The total pressure of the container is $18 \ atm$. What are the partial pressures $P_A$ and $P_B$ respectively?