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 Chemistry · Topic 6 of 11
Topic 6: The rate and extent of chemical change – GCSE AQA Higher 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 Chemistry. 16 lessons in 2 subtopics.
Revise Topic 6: The rate and extent of chemical change for GCSE AQA Higher Chemistry, including Rate of reaction. 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?: Learn what catalysts are, how they work by lowering activation energy, and understand their role in biological systems as enzymes. Explore how catalysts provide alternative reaction pathways.
- Identifying catalysts and reaction profiles: Learn how to identify catalysts in chemical reactions, interpret reaction profile diagrams for catalysed reactions, and understand why catalysts don't appear in chemical equations.
- What affects how fast reactions happen?: Learn about the five key factors that control reaction rates: concentration, pressure, surface area, temperature, and catalysts. Understand how changing each factor speeds up or slows down chemical reactions.
- Understanding Collision Theory and Activation Energy: Learn the fundamental principles of collision theory, including what activation energy is and how successful collisions lead to chemical reactions.
- How Concentration, Pressure and Temperature Affect Reaction Rate: Explore how changing concentration, pressure and temperature affects collision frequency and energy, and predict their effects on reaction rates using collision theory.
- Surface Area Effects and Using Proportionality in Collision Theory: Understand how particle size and surface area to volume ratio affects reaction rates, and apply proportionality concepts when explaining collision theory effects.
- Calculating Mean Rate of Reaction: Learn to calculate the mean rate of a reaction using the quantity of reactant used or product formed over time. Practice using the rate equations and understand different units for measuring quantity and rate.
- Rate Graphs and Tangents: Draw and interpret graphs showing reactant used or product formed against time. Learn to draw tangents to curves and calculate gradients to measure instantaneous rates of reaction.
Reversible reactions and dynamic equilibrium
- How Temperature Changes Affect Chemical Equilibrium: Explore how increasing and decreasing temperature affects the position of equilibrium for endothermic and exothermic reactions, and learn to predict these changes using given data.
- How concentration changes affect equilibrium: Learn how changing the concentration of reactants or products disrupts equilibrium and causes the system to shift until a new equilibrium is established.
- Predicting equilibrium shifts from data: Practice interpreting data and predicting how concentration changes will affect equilibrium positions in chemical reactions.
- How Pressure Changes Affect Equilibrium Position: Learn how increasing and decreasing pressure shifts equilibrium towards sides with different numbers of gas molecules, and practice interpreting data to predict pressure effects on gaseous reactions.
- Understanding Equilibrium Systems and Le Chatelier's Principle: Explore how the amounts of reactants and products at equilibrium depend on reaction conditions, and discover how equilibrium systems respond to changes by counteracting them using Le Chatelier's Principle.
- Predicting Changes in Equilibrium Systems: Apply Le Chatelier's Principle to make qualitative predictions about how changes in temperature, pressure, and concentration affect systems at equilibrium.
- Understanding Reversible Reactions: Learn what reversible reactions are, how they are represented using chemical equations, and how changing conditions can affect the direction of these reactions.
- Dynamic Equilibrium in Closed Systems: Understanding how reversible reactions reach equilibrium when forward and reverse reaction rates become equal in closed apparatus.
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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 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.