Consider the gaseous reversible reaction, A+2B⇌2C+D occuring in a one litre closed vessel. Initially 1 mole of ‘A’ and 2 moles of ‘B’ are taken. At equilibrium 1 mole of ‘C’ is formed. Value of equilibrium constant Kc  is

A      +    2B     ⇌       2C  +  Dinitial moles                       1                2                   -      -moles at equilibrium   (1-0.5)         (2-1)          1       0.5Kc=[C]2[D][A] [B]2 Kc=[1]2[0.5][0.5] [1]2 Kc=1