R1.1.2 Endothermic and exothermic reactions

Key concepts to master

• R1.1.2 Endothermic and exothermic reactions should be understood as a core IB Chemistry HL idea, not just a definition to memorize. Aim to explain what it means, where it appears in the syllabus, and why it matters in exam answers.
• High-scoring responses on R1.1.2 Endothermic and exothermic reactions usually connect the main concept to subject-specific terminology, clear cause-and-effect reasoning, and accurate examples taken from class content or past-paper style scenarios.
• Revision works best when you move between three layers: the core idea itself, the evidence or examples that support it, and the common exam wording used to assess it.

How to study this topic

1. 1

   Start with a one-sentence definition of R1.1.2 Endothermic and exothermic reactions in your own words, then expand it using the exact terminology expected in IB Chemistry HL.

2. 2

   Use the resources on this page to separate factual recall from application. First learn the idea, then practise using it in short structured responses.

3. 3

   Review R1.1.2 Endothermic and exothermic reactions alongside nearby topics in Chemistry HL so you can compare concepts, avoid mixing terminology, and understand how the topic is framed across the syllabus.

Common mistakes

• Giving a memorized definition of R1.1.2 Endothermic and exothermic reactions without showing how it works in context or why it matters in IB Chemistry HL.
• Confusing R1.1.2 Endothermic and exothermic reactions with closely related terms from the same unit, especially when the question asks you to compare, explain, or evaluate.
• Skipping examples, evidence, or exam command terms, which makes answers sound generic even when the core idea is correct.

Study prompts

• Explain the significance of R1.1.2 Endothermic and exothermic reactions in IB Chemistry HL.
• Compare R1.1.2 Endothermic and exothermic reactions with a related concept from the same Chemistry HL unit.
• Describe one example or scenario that shows how R1.1.2 Endothermic and exothermic reactions works in practice.
• Identify one common misunderstanding about R1.1.2 Endothermic and exothermic reactions and explain how to avoid it in an exam answer.