For the reaction, N (g) O (g) 2NO(g) , the equilibrium constant is K1. The equilibrium constant is K2 for the reaction, 2NO(g) O (g) 2NO (g) . What is K for the reaction NO (g) N (g) O (g) (AIPMT 2011) (a) (K K ) (b) (2K K ) (c) (4K K ) (d) 1/ 2 K K

The reaction (1) and (2) are added and then they are reversed. The net reaction will be divided by 2 to obtain the final reaction. 2 2 2 1 NO (g) N (g) O (g) 2 Hence, the expression for the final reactions will be 1 2 1 K= K .K Hence, the correct answer is option (d)