Question

An equilibrium mixture of so2, o2, and so3 gases is determined to consist of 2 mol/l so2, 1 mol/l o2, and 4 mol/l so3. what is the equilibrium constant for the system at this temperature? the balanced equation for this reaction is

Answer 1

The all substances that participate in the reaction are in gaseous phase and the given data are the concentrations when the reaction at equilibrium. Hence, we can use that given concentrations directly to find out the equilibrium constant, Kc.

The balanced equation for the equilibrium is,

2SO₂(g) + O₂(g) ⇄ 2SO₃(g)

Kc = [SO₃(g)]² / [SO₂(g)]² [O₂(g)]
Kc = (4 mol/L)² / (2 mol/L)² (1 mol/L)
Kc = 4 mol⁻¹ L

Hence, the equilibrium constant is 4 mol⁻¹ L