Chemical and Ionic Equilibrium - Result Question 18
18. Consider the following equilibrium in a closed container
$ N _2 O _4(g) \rightleftharpoons 2 NO _2(g) $
At a fixed temperature, the volume of the reaction container is halved. For this change, which of the following statements hold true regarding the equilibrium constant $\left(K _p\right)$ and degree of dissociation $(\alpha)$ ?
(2002,3 M)
(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
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Answer:
Correct Answer: 18. (d)
Solution:

At constant temperature, halving the volume will change both $p$ and $\alpha$ but $K_p$ remains constant.