What is the equilibrium concentration of each of the substances in the equilibrium when the initial concentration of ICl was 0.78 M?
2ICl (g) ⇌ I2 (g) + Cl2 (g); Kc= 0.14
For the given reaction, let’s assume that the molar concentration of I2 and Cl2 at equilibrium is x mol/L.
The given reaction is
2ICl (g) ⇌ I2 (g) + Cl2 (g)
Initial concentration 0.78M 0 0
Equilibrium concentration (0.78-2x)M x x
Equilibrium constant (Kc) is defined as a number that expresses the relationship between the amounts of products and reactants present at equilibrium in a reversible chemical reaction at a given temperature.
Here, Kc = 0.14
For the given reaction,
Where, [I2]=concentration of I2 in mol/L at equilibrium
[Cl2]=concentration of Cl2 in mol/L at equilibrium
[ICl]=concentration of ICl in mol/L at equilibrium
X = 1.67
Therefore, at equilibrium,
[H2]=[I2]=0.167 M
[ICl]= 0.78 - (2x0.167) = 0.446 M