The Equilibrium Constant

Part of the Energy, Rates and Equilibrium section of Coddy's Chemistry journey. Lesson 23 of 35.

The equilibrium constant: products over reactants, each to the power of its coefficient.

$K = \frac{[\mathrm{C}]^c [\mathrm{D}]^d}{[\mathrm{A}]^a [\mathrm{B}]^b}$

For N₂ + 3H₂ ⇌ 2NH₃:

$K = \frac{[\mathrm{NH_3}]^2}{[\mathrm{N_2}][\mathrm{H_2}]^3}$

One value at a given temperature. Large: mostly products. Small: mostly reactants.

Challenge

Ammonia is made by the Haber process. Build its equilibrium constant expression.

Try it yourself

EquilibriumWrite the equilibrium expression

N₂(g)3 H₂(g)2 NH₃(g)

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Energy, Rates and Equilibrium

1Energy in Reactions

4Rates of Reaction

7Practice Problems

2Bond Energies

5Equilibrium

3Changes of State

6Changing an Equilibrium