If $PCl_{5(g)}$ is $40\%$ dissociated at equilibrium at $27\,^{\circ}C$ and $1\, atm$,then calculate the density of the equilibrium mixture at $27\,^{\circ}C$ and $1\, atm$ for the reaction: $PCl_{5(g)} \rightleftharpoons PCl_{3(g)} + Cl_{2(g)}$ (in $g\,L^{-1}$)

Consider the following reaction in a sealed vessel at equilibrium with concentrations of $N_2 = 3.0 \times 10^{-3} \ M$,$O_2 = 4.2 \times 10^{-3} \ M$,and $NO = 2.8 \times 10^{-3} \ M$.
$2 \ NO_{(g)} \rightleftharpoons N_{2_{(g)}} + O_{2_{(g)}}$
If $0.1 \ mol \ L^{-1}$ of $NO_{(g)}$ is taken in a closed vessel,what will be the degree of dissociation $(\alpha)$ of $NO_{(g)}$ at equilibrium?

For the reaction $A \rightleftharpoons nB$,if $a$ moles of $A$ are taken initially and $x$ moles of $A$ dissociate at equilibrium,find the value of the degree of dissociation.

What is the vapour density of $O_2$ gas?

Phosphine decomposes at $300 \ K$ and $3 \ atm$ as
$4PH_{3(g)} \rightleftharpoons P_{4(g)} + 6H_{2(g)}$
Calculate the vapour density of phosphine if it dissociates to the extent of $30 \%$.

The density of air is $0.00130 \, g/mL$. What will be the vapor density of air?