Chemistry

Equilibrium Constant Kc

Write the expression for concentration equilibrium constant.

Kc = [Products] / [Reactants] (with stoichiometric powers)

Formula Explanation

Kc is the ratio of product of concentrations of products to reactants, each raised to their coefficients.

Variables Explained

[ ] = equilibrium concentrations.

Solved Example

For N₂ + 3H₂ ⇌ 2NH₃, write Kc.
Kc = [NH₃]² / ([N₂][H₂]³).

Exam Tip

Pure solids and liquids do not appear in Kc.