During a chemical reaction, the bonds within reactant molecules are broken and new bonds are formed to create the products.
Which row in the table correctly describes the energy changes involved in these two processes?
| Breaking chemical bonds | Making chemical bonds | |
|---|---|---|
| A | Exothermic (releases energy) | Exothermic (releases energy) |
| B | Exothermic (releases energy) | Endothermic (absorbs energy) |
| C | Endothermic (absorbs energy) | Exothermic (releases energy) |
| D | Endothermic (absorbs energy) | Endothermic (absorbs energy) |
Row A
Row B
Row C
Row D
94 exam-style questions on Edexcel GCSE Chemistry 8.2 Heat energy changes in chemical reactions, covering 8.2.1 Exothermic and endothermic changes, 8.2.2 Bond breaking, bond making and overall energy change, 8.2.3 Calculating energy change from bond energies, and 8.2.4 Activation energy and reaction profiles. Each one has a worked solution and a mark scheme showing where the marks go.