Exam Tips: Rates of Reaction
Part of Rates & Collision Theory — GCSE Chemistry
This exam tips covers Exam Tips: Rates of Reaction within Rates & Collision Theory for GCSE Chemistry. Revise Rates & Collision Theory in Rates of Reaction for GCSE Chemistry with 20 exam-style questions and 16 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 12 of 13 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
Topic position
Section 12 of 13
Practice
20 questions
Recall
16 flashcards
💡 Exam Tips: Rates of Reaction
🎯 Common Question Types:
- Explain why rate increases when temperature rises (3 marks)
- Describe what a rate graph shows (2 marks)
- Calculate rate from a graph tangent (2 marks)
- Describe the required practical method (4 marks)
📝 Key Command Words:
- Explain: Give the collision theory mechanism — say "successful collisions"
- Describe: State what the graph shows — gradient, final value
- Calculate: Use Rate = change ÷ time, show units
⚠️ Common Mistakes to Avoid:
- Saying "particles have more energy" without specifying kinetic energy
- Forgetting to mention "successful collisions" in explain questions
- Confusing rate (speed of reaction) with amount of product
Quick Check: What two conditions must be met for a collision to be successful?
The colliding particles must have energy greater than or equal to the activation energy, AND they must collide with the correct orientation.
Quick Check: On a rate graph, what does the steepness of the curve represent, and what does the horizontal plateau represent?
The steepness (gradient) represents the rate of reaction — steeper means faster. The horizontal plateau means the reaction has stopped (a reactant has been used up).
Quick Check: A reaction produces 24 cm³ of gas in 60 seconds. Calculate the rate of reaction.
Rate = 24 ÷ 60 = 0.4 cm³/s