Which of the following will have the highest degree of dissociation for $4-$nitrophenol in an aqueous solution (in $M$)?

The dissociation equilibrium of a gas $AB_{2}$ can be represented as:
$2AB_{2(g)} \rightleftharpoons 2AB_{(g)} + B_{2(g)}$
The degree of dissociation is $x$ and is small compared to $1$. The expression relating the degree of dissociation $(x)$ with equilibrium constant $K_P$ and total pressure $P$ is:

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 $g\,L^{-1}$)

For the equations $(i) \ HCN + CCl_4 \rightarrow \alpha_1$ and $(ii) \ HCN + C_6H_6 \rightarrow \alpha_2$,which degree of dissociation is greater,$\alpha_1$ or $\alpha_2$?

Vapour density of a gas is $5.6$,volume of $5.6 \ g$ of it at $STP$ is ............... $L$

If the density of air at $STP$ is $0.001293 \, g \, mL^{-1}$,what will be its vapor density?