Q.

For the following gas phase equilibrium reaction at constant temperature,

NH3(g)12N2(g)+32H2(g)

if the total pressure is 3 atm and the pressure equilibrium constant (Kp) is 9 atm, then the degree of dissociation is given as (x×10-2)-1/2. The value of x is ______.(nearest integer)                       [2026]


Ans.

(125)

NH3(g)12N2(g)+32H2(g)t=01 mole--t=teq1-αα/23α/2

Kp=(α2)1/2(3α2)3/2(1-α)[PT1+α]1                  [PT=3 atm]

9=(α2)1/2(3α2)3/2(1-α)×(3)1/21+α

9=9(α2)21-α2

1-α2=α24

5α24=1

α2=0.8

α=(0.8)1/2

α=[10.8]-1/2

α=[125×10-2]-1/2

x=125