I2 + Cl2 →2ICl Kp=81.9. A reaction mixture initially P(I2)=P(Cl2)=P(ICl)= 0.1 atm. How to determine the direction of the reaction will proceed?

1 Answer
Dec 9, 2015

The equilibrium will shift to the right.

Explanation:

The equilibrium in question is the following:

I2+Cl22ICl KP=81.9

The expression of KP is: KP=P2IClPI2PCl2

Since we have the initial pressures, we will determine the direction of the equilibrium from the reaction quotient QP.

The expression of QP is: QP=(P0)2ICl(P0)I2(P0)Cl2

QP=(0.1)2(0.1)×(0.1)=1<KP

Since QP<KP then the equilibrium will shift to the right to increase the pressure of the product (numerator) and decrease the pressure of reactants (denominator).