Question

The following reaction is found to be at equilibrium at 25 celcius: 2SO3--->O2 + 2SO2 + 198kJ/mol.
What is the expression for the equilibrium constant, Kc?
A.) [SO3]^2/[O2][SO2]^2
B.) 2[SO3]/[O2]2[SO2]
C.) [O2][SO2]^2/[SO3]^2
D.) [O2]2[SO2]/2[SO3]

Answer 1

Answer:

C.) [O₂][SO₂]²/[SO₃]²

Explanation:

Let's consider the following reaction.

2 SO₃(g) ⇄ O₂(g) + 2 SO₂(g)

The equilibrium constant (Kc) is the product of the concentration of the products raised to their stoichiometric coefficients divided by the product of the concentration of the reactants raised to their stoichiometric coefficients.

$Kc=\frac{[O_{2}].[SO_{2}]^{2} }{[SO_{3}]^{2} }$