Consider the following equilibrium in a closed container:
`N_(2)O_(4)(g)hArr2NO_(2)(g)`
At a fixed temperature, the volume of the reaction container is halved. For this change which of the following statements holds true regarding the equilibrium constant `(K_(p))` and the degree of dissociation `(alpha)`?

Options

A. neither `K_(P)` nor `alpha` changes
B. both `K_(P)` and `alpha` change
C. `K_(P)` changes, but `alpha ` does not change
D. `K_(P)` does not change but `alpha ` changes

Answer

D

Explanation

`N_(2)O_(4)(g)hArr2NO_(2)`.
`{:("moles"t=0,1,0),("moles at eq.",1-alpha,2alpha):}`
`K_(P)=((2alpha)/((1+alpha))xxP)^(2)/((1-alpha)/(1+alpha)xxP)=(4alpha^(2))/(1-alpha^(2))xxP`.
When volume is halved, `P` is double.
`therefore alpha` will change a `K_(P)` is independent of pressure change.