Embibe Experts Solutions for Chapter: States of Matter: Gases and Liquids, Exercise 3: Level 3

Assertion: Van der Waals equation describes the behaviour of real gases.

Reason: The kinetic theory postulates that negligible volume of gaseous molecules and intermolecular forces of attraction do not stand correct at high pressure and low temperature.

Van der Waals equation may be reduced to the following form:
$\mathrm{Z}=1+\left(\mathrm{b}-\frac{\mathrm{a}}{\mathrm{RT}}\right)\frac{1}{\overline{\mathrm{V}}}+{\left(\frac{\mathrm{b}}{\overline{\mathrm{V}}}\right)}^2+\dots$
This equation shows that (tick the incorrect one):

A gas at ${\mathrm{T}}_2°$ is condensed to a liquid, following the path $\mathrm{XYAB}$. The liquid appears at the point:

The ratio between the $\mathrm{rms}$ velocity of ${\mathrm{H}}_2$ at $50 \mathrm{K}$ and that of ${\mathrm{O}}_2$ at $800 \mathrm{K}$ is

$\mathrm{X} \mathrm{mL}$ of ${\mathrm{H}}_2$ gas effuses through a hole in a container in $5$ $\mathrm{seconds}$. The time taken for the effusion of the same volume of the gas specified below under identical conditions is

A sample of natural gas is $85.2\%$ of methane (${\mathrm{CH}}_4$) and $14.8\%$ of ethane (${\mathrm{C}}_2{\mathrm{H}}_6$) by mass. What would be the density $\left(\mathrm{in} \mathrm{g}/\mathrm{L}\right)$ of this mixture at $18°\mathrm{C}$ and $748 \mathrm{mmHg}$?

Answer by rounding off up to two places of decimals.

The vapour pressure of water at $20°\mathrm{C}$ is $17.5 \mathrm{mm} \mathrm{Hg}$. Calculate the mass of water (in mg) per litre of air at $20°\mathrm{C}$ and $45\%$ relative humidity. $\left(\mathrm{R}=0.0821 \mathrm{atm} \mathrm{L} {\mathrm{mol}}^{-1} {\mathrm{K}}^{-1}\right)$

Answer correct up to two places of decimals.

The composition of the equilibrium mixture ${\mathrm{Cl}}_2\rightleftharpoons 2\mathrm{Cl}$, which is attained at $1200°\mathrm{C},$ is determined by measuring the rate of effusion through a pinhole. It is observed that at $1.80 \mathrm{mmHg}$ pressure, the mixture effuses $1.16$ times as fast as krypton effuses under the same conditions. Calculate the fraction of chlorine molecules dissociated into atoms. (Atomic weight of $\mathrm{Kr}=84$)

Round off your answer up to two places of decimals.