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 .....$atm$.

The ratio of the rate of diffusion of helium and methane under identical conditions of pressure and temperature will be

At $27^{\circ} C$, a closed vessel contains a mixture of equal weights of helium (mol. wt. = $4$), methane (mol. wt. = $16$) and sulphur dioxide (mol. wt. = $64$). The pressure exerted by the mixture is $210 \ mm$. If the partial pressures of helium, methane and sulphur dioxide are $p_1, p_2$ and $p_3$ respectively, which one of the following is correct?

$A$ closed container contains a mixture of non-reacting gases $A$ and $B$. The partial pressures of $A$ and $B$ are $4.5 \ bar$ and $5.5 \ bar$ respectively. Find the mole fractions of $A$ and $B$ respectively.

Explain the effect of increasing the temperature of a liquid on the intermolecular forces operating between its particles. What will happen to the viscosity of a liquid if its temperature is increased?

At constant volume and temperature conditions,the rate of diffusion $D_A$ and $D_B$ of gases $A$ and $B$ having densities $\rho_A$ and $\rho_B$ are related by the expression: