Question

Pure NOCl gas was heated at 240°C in a 1.00−L container. At equilibrium the total pressure was 1.00 atm and the NOCl pressure was 0.64 atm. 2NOCl(g) ⇆ 2NO(g) + Cl2(g) (a) Calculate the partial pressure of NO and Cl2 in the system. b) Calculate the equilibrium constant KP.

Answer 1

ans)

from above data that

given equation is :

2 NOCl(g) -------> 2NO (g) + Cl2(g)

we can written as I.C. E table
I: a 0 0

C: - 2x +2x +x

E: a-2x 2x x

At equilibrium total pressure = 1.0 atm

a + x = 1.0 atm

a- 2x = 0.64 atm

solving the above TWO equations we get :
x = 0.12 atm

a = 0.88 atm

from reaction

2x is the pressure of NO =2*0.12=0.24 , x=Cl2=0.12

Partialpressure of NO = 1.0 atm x 0.24 /1

=0.24 atm

Partial pressure of Cl2 = 1.0 atm x 0.12 / 1

= 0.12 atm

Given theequilibrium pressure of the gas = 0.64 atm

We know that

Kp= P2 (NO) P (Cl2) / P2 (NOCl)

substitute values in above equation

= (0.24)2 (0.12) / ( 0.64)2

Kp= 0.0168

Partialpressure of NO =0.24 atm

Partial pressure of Cl2 = 0.12 atm