What this topic covers
Topic 6: The rate and extent of chemical change has 2 subtopics:
- Rate of reaction
- Reversible reactions and dynamic equilibrium
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GCSE AQA Higher Combined Science Chemistry · Topic 6 of 11
Topic 6: The rate and extent of chemical change – GCSE AQA Higher Combined Science Chemistry revision notes
Choose a subtopic. Topic 6: The rate and extent of chemical change covers Rate of reaction and Reversible reactions and dynamic equilibrium in GCSE AQA Higher Combined Science Chemistry. 16 lessons in 2 subtopics.
Revise Topic 6: The rate and extent of chemical change for GCSE AQA Higher Combined Science Chemistry. 16 lessons across 2 subtopics.
16
Lessons
2
Subtopics
Topic 6: The rate and extent of chemical change lessons by subtopic
16 lessons, grouped by subtopic.
Rate of reaction
- What are catalysts and how do they work?
- Identifying catalysts and reaction profiles
- What affects how fast reactions happen?
- Understanding Collision Theory and Activation Energy
- How Concentration, Pressure and Temperature Affect Reaction Rate
- Surface Area Effects and Using Proportionality in Collision Theory
- Calculating Mean Rate of Reaction
- Rate Graphs and Tangents
Reversible reactions and dynamic equilibrium
- How Temperature Changes Affect Chemical Equilibrium
- How concentration changes affect equilibrium
- Predicting equilibrium shifts from data
- How Pressure Changes Affect Equilibrium Position
- Understanding Equilibrium Systems and Le Chatelier's Principle
- Predicting Changes in Equilibrium Systems
- Understanding Reversible Reactions
- Dynamic Equilibrium in Closed Systems
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Frequently asked questions
What is Topic 6: The rate and extent of chemical change?
Topic 6: The rate and extent of chemical change covers Rate of reaction and Reversible reactions and dynamic equilibrium in GCSE AQA Higher Combined Science Chemistry. 16 lessons in 2 subtopics.
What is a catalyst?
A catalyst is a substance that increases the rate of a chemical reaction without being used up in the reaction. The What are catalysts and how do they work? notes cover this in full.
What are enzymes?
Enzymes are biological catalysts made of protein that speed up specific reactions in living organisms. The What are catalysts and how do they work? notes cover this in full.
Why are reversible reactions important?
Reversible reactions are the basis of major industrial processes, such as the Haber process for making ammonia. The Understanding Reversible Reactions notes cover this in full.
What factors affect the rate of reaction?
The five factors that affect the rate of reaction are the concentration of reactants in solution, the pressure of reacting gases, the surface area of solid reactants, temperature, and the presence of a catalyst. The What affects how fast reactions happen? notes cover this in full.
What is collision theory?
Collision theory explains that chemical reactions occur only when particles collide with sufficient energy and the correct orientation. The Understanding Collision Theory and Activation Energy notes cover this in full.
What are the units for rate of reaction?
The units for rate of reaction depend on what is measured: g/s for mass, cm³/s for gas volume and mol/s for amount of substance. The Calculating Mean Rate of Reaction notes cover this in full.
What is dynamic equilibrium?
Dynamic equilibrium is the state reached when the forward and reverse reactions occur at exactly the same rate in a closed system. The Dynamic Equilibrium in Closed Systems notes cover this in full.
What is rate of reaction?
Rate of reaction is how fast reactants are used up or products are formed in a chemical reaction, measured in units such as g/s or mol/s. The What affects how fast reactions happen? notes cover this in full.