Enthalpy Change

Part of the Energy, Rates and Equilibrium section of Coddy's Chemistry journey. Lesson 3 of 35.

The enthalpy change $\Delta H$ is the heat given out or taken in, in kJ per mole of reaction as written.

Exothermic: Δ H < 0. Endothermic: Δ H > 0.

The heat is in proportion to the amount:

$Q = n \times \Delta H$

Challenge

Propane, C₃H₈, burns in a camping stove: $\Delta H = -2220\ \mathrm{kJ/mol}$ . What is the heat change $Q$ when $0.5\ \mathrm{mol}$ of propane burns?

Try it yourself

Solve for $Q$

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