NEET Solved Paper 2017 Question 1

Question: The equilibrium constants of the following are. $ N _2+3H _2\rightarrow 2NH _3,K _4 $ $ N _2+O _2\rightarrow 2NO,K _2 $ $ H _2+\frac{1}{2}O _2\xrightarrow{{}}H _2O,K _3 $ The equilibrium constant (K) of the reaction $ 2NH _3+\frac{5}{2}O _2\xrightarrow{k}2NO+3H _2O, $ will be

Options:

A) $ K_2^{3}K _3/K _1 $

B) $ K _1K_3^{3}/K _2 $

C) $ K _2K_3^{3}/K _1 $

D) $ K _2K _3/K _1 $

Show Answer

Answer:

Correct Answer: C

Solution:

  • (i) $ N _2+3H _22NH _3;K _1=\frac{{{[NH _3]}^{2}}}{[N _2]{{[H _2]}^{3}}} $
    (ii) $ N _2+O _22NO;K _2=\frac{{{[NO]}^{2}}}{[N _2][O _2]} $
    (iii) $ H _2+\frac{1}{2}O _2\xrightarrow{{}}H _2O;$

    $K _3=\frac{[H _2O]}{[H _2]{{[O _2]}^{1/2}}} $ $ (II+3\times III-II) $ will give $ 2NH _3+\frac{5}{2}O _22NO+3H _2O; $
    $ \therefore $ $ K=K _2\times K_3^{3}/K _1 $