Rates of ReactionTopic Summary
Topic Summary: Dynamic Equilibrium & Le Chatelier's Principle
Part of Equilibrium (HT) — GCSE Chemistry
This topic summary covers Topic Summary: Dynamic Equilibrium & Le Chatelier's Principle within Equilibrium (HT) for GCSE Chemistry. Revise Equilibrium (HT) in Rates of Reaction for GCSE Chemistry with 20 exam-style questions and 15 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 13 of 13 in this topic. Use this topic summary to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 13 of 13
Practice
20 questions
Recall
15 flashcards
Topic Summary: Dynamic Equilibrium & Le Chatelier's Principle
Key Terms
- Dynamic equilibrium — forward rate = backward rate
- Closed system — required for equilibrium
- Le Chatelier's Principle — system opposes change
- Equilibrium position — left (reactants) or right (products)
Le Chatelier Quick Rules
- Temp ↑ → endothermic direction
- Temp ↓ → exothermic direction
- Conc of reactant ↑ → shift right
- Pressure ↑ → fewer gas molecules side
- Catalyst → no shift (faster equilibrium)
Haber Process
- N₂ + 3H₂ ⇌ 2NH₃ (exothermic forward)
- Temperature: 450°C (compromise)
- Pressure: 200 atm (compromise)
- Catalyst: iron
- High P → more NH₃ (4→2 gas moles)
Common Exam Errors
- Saying equal concs at equilibrium
- Catalyst shifts equilibrium (wrong)
- Not counting gas molecules for pressure
- Missing "closed system" in definition