Le Chatelier's Principle

Part of the Energy, Rates and Equilibrium section of Coddy's Chemistry journey. Lesson 27 of 35.

Le Chatelier's principle: a disturbed equilibrium shifts to partly undo the change.

Add a reactant or remove a product: it shifts right, toward the products.

$\mathrm{N_2(g)} + 3\mathrm{H_2(g)} \rightleftharpoons 2\mathrm{NH_3(g)} \qquad \Delta H = -92\ \mathrm{kJ}$

The shift only lessens the change; a new equilibrium settles.

Challenge

In a Haber reactor at equilibrium,

$\mathrm{N_2(g)} + 3\mathrm{H_2(g)} \rightleftharpoons 2\mathrm{NH_3(g)} \qquad \Delta H = -92\ \mathrm{kJ}$

more nitrogen is pumped in. Which way does the equilibrium shift?

Try it yourself

EquilibriumWhich way does it shift?

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