What this topic covers
Topic C5: Monitoring and controlling chemical reactions has 2 subtopics:
- Controlling reactions
- Equilibria
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GCSE OCR Higher Combined Science Chemistry · Topic 5 of 6
Topic C5: Monitoring and controlling chemical reactions – GCSE OCR Higher Combined Science Chemistry revision notes
Choose a subtopic. Topic C5: Monitoring and controlling chemical reactions covers Controlling reactions and Equilibria in GCSE OCR Higher Combined Science Chemistry. 21 lessons in 2 subtopics.
Revise Topic C5: Monitoring and controlling chemical reactions for GCSE OCR Higher Combined Science Chemistry, including Controlling reactions and Equilibria.
21
Lessons
2
Subtopics
Topic C5: Monitoring and controlling chemical reactions lessons by subtopic
21 lessons, grouped by subtopic.
Controlling reactions
- Calculating Mean Rate of Reaction
- Rate Graphs and Tangents
- 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
- What are catalysts and how do they work?
- Identifying catalysts and reaction profiles
- Understanding Acid Strength and Concentration
- pH Scale and Hydrogen Ion Concentration
Equilibria
- Understanding Reversible Reactions
- Introduction to the Haber Process
- Equilibrium and Rate in the Haber Process
- Energy Changes in Reversible Reactions
- Dynamic Equilibrium in Closed Systems
- Understanding Equilibrium Systems and Le Chatelier's Principle
- Predicting Changes in Equilibrium Systems
- How concentration changes affect equilibrium
- Predicting equilibrium shifts from data
- How Temperature Changes Affect Chemical Equilibrium
- How Pressure Changes Affect Equilibrium Position
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Frequently asked questions
What is Topic C5: Monitoring and controlling chemical reactions?
Topic C5: Monitoring and controlling chemical reactions covers Controlling reactions and Equilibria in GCSE OCR Higher Combined Science Chemistry. 21 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 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 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 is the pH scale?
The pH scale is a logarithmic scale from 0 to 14 that measures hydrogen ion concentration: pH 7 is neutral, lower values are acidic and higher values are basic (alkaline). The pH Scale and Hydrogen Ion Concentration 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.