Chemistry - Chemical Equilibrium Question with Solution | TestHub

$$\begin{array}{c}\text{Initial}\text{moles}\text{1,}\text{at}\text{equilibrium:}{\text{N}}_{\text{2}}{\text{O}}_{\text{5}}\text{=}\text{1}\text{-}\alpha \text{,}{\text{NO}}_{\text{2}}\text{=}\text{2}\alpha \text{,}{\text{O}}_{\text{2}}\text{=}\alpha \text{/2}\text{Total}\text{moles}\text{=}\\ \text{1}\text{+}\text{1.5}\alpha \\ \text{Mass}\text{is}\text{conserved,}\text{so}{\text{M/M}}_{\text{avg}}\text{=}\text{1}\text{+}\text{1.5}\alpha \text{with}{\text{M}}_{\text{avg}}\text{=}\text{2D}\\ \text{1}\text{+}\text{1.5}\alpha \text{=}\text{M/(2D)}\\ \text{At}\text{constant}\text{V}\text{and}\text{T,}\text{pressure}\text{is}\text{proportional}\text{to}\text{moles:}\text{P}\text{=}{\text{P}}_{\text{o}}\text{(1}\text{+}\text{1.5}\alpha \text{)}\text{=}{\text{P}}_{\text{o}}\\ \text{M/(2D),}\text{so}\text{(a)}\text{is}\text{correct}\\ \alpha \text{=}\text{(M}\text{-}\text{2D)/(3D),}\text{so}\text{(b)}\text{is}\text{correct}\\ {\text{P}}_{\text{N2O5}}\text{=}{\text{P}}_{\text{o}}\text{(1}\text{-}\alpha \text{)}\text{=}{\text{P}}_{\text{o}}\text{(3D}\text{-}\text{M}\text{+}\text{2D)/(3D)}\text{=}\text{(5D}\text{-}{\text{M)P}}_{\text{o}}\text{/(3D),}\text{so}\text{(c)}\text{is}\text{correct}\\ {\text{P}}_{\text{O2}}\text{=}{\text{P}}_{\text{o}}\alpha \text{/2}\text{=}\text{(M}\text{-}{\text{2D)P}}_{\text{o}}\text{/(6D),}\text{which}\text{is}\text{not}\text{(M}\text{-}{\text{2D)P}}_{\text{o}}\text{/(3D),}\text{so}\text{(d)}\text{is}\\ \text{incorrect}\\ \text{The}\text{correct}\text{options}\text{are}\text{(a),}\text{(b)}\text{and}\text{(c).}\end{array}$$