# Introduction and Energy Changes

> This section is heat of reaction (ΔH), exothermic and endothermic reactions, and energy changes related to bond energy. You define the three official terms, then classify a reaction with a reason…

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## Full notes

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## More in Rate and Extent of Reactions

- [Activation Energy and Catalysts](https://www.hlayiso.com/grade-12/physical-sciences/notes/rate-and-extent-of-reactions/activation-energy-and-catalysts) — Next section
- [All Rate and Extent of Reactions sections](https://www.hlayiso.com/grade-12/physical-sciences/notes/rate-and-extent-of-reactions)

## Frequently asked questions

### What will I learn in "Introduction and Energy Changes"?

This section covers Introduction and Energy Changes as part of Rate and Extent of Reactions in Grade 12 Physical Sciences. You'll find clear explanations, worked examples, and key definitions aligned to the CAPS curriculum.

### Is this section aligned with the CAPS curriculum?

Yes. All notes on Hlayiso, including "Introduction and Energy Changes", are written against the official CAPS curriculum and ATP for Grade 12 Physical Sciences.

### What should I study after "Introduction and Energy Changes"?

Continue with the next section in Rate and Extent of Reactions, or test your understanding with the interactive quiz linked to this section.

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