What this topic covers
Topic C3: Chemical reactions has 4 subtopics:
- Introducing chemical reactions
- Energetics
- Types of chemical reactions
- Electrolysis
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GCSE OCR Higher Combined Science Chemistry · Topic 3 of 6
Topic C3: Chemical reactions – GCSE OCR Higher Combined Science Chemistry revision notes
Choose a subtopic. Topic C3: Chemical reactions covers Introducing chemical reactions, Energetics, Types of chemical reactions, and Electrolysis in GCSE OCR Higher Combined Science Chemistry. 46 lessons in 4 subtopics.
Revise Topic C3: Chemical reactions for GCSE OCR Higher Combined Science Chemistry, including Introducing chemical reactions. 46 lessons across 4 subtopics.
46
Lessons
4
Subtopics
Topic C3: Chemical reactions lessons by subtopic
46 lessons, grouped by subtopic.
Introducing chemical reactions
- The Law of Conservation of Mass
- Balancing Chemical Equations
- Introduction to Moles and Avogadro's Constant
- Molar Mass and Converting Between Moles and Mass
- Testing for hydrogen gas
- Testing for Oxygen Gas
- Testing for Carbon Dioxide Gas
- Testing for Chlorine Gas
- Understanding Chemical Equations in Terms of Moles
- Calculating Masses from Balanced Chemical Equations
- Explaining Mass Changes in Open Systems
- Converting Masses to Moles for Equation Balancing
- Balancing Equations from Mass Data
- Understanding Solution Concentration
- Calculating Mass of Solute in Solutions
- Understanding Uncertainty in Chemical Measurements
- Understanding Limiting Reactants
- Understanding Electrode Reactions in Electrolysis
- Writing Half Equations for Electrode Reactions
Energetics
- Understanding Exothermic and Endothermic Reactions
- Examples and Applications of Energy Transfer Reactions
- Drawing and Understanding Reaction Profiles
- Activation Energy and Collision Theory
- Breaking and Forming Bonds
- Calculating Energy Changes Using Bond Energies
- Explaining Exothermic and Endothermic Reactions
Types of chemical reactions
- Metal Oxides and Oxidation Reactions
- Acid-Metal Reactions: Products and Patterns
- Redox in Acid-Metal Reactions
- What Salts Are Produced in Neutralisation?
- Neutralisation Reactions and Salt Formulae
- Metal Reactions and the Reactivity Series
- Displacement Reactions and the Extended Reactivity Series
- Making Soluble Salts from Acids
- Crystallising Salt Solutions and Making Pure Samples
- Understanding the pH Scale
- Acids, Alkalis and Neutralisation
Electrolysis
- Understanding Electrolytes and Ion Movement
- Writing Half Equations for Electrolysis
- Products of Electrolysis in Molten Ionic Compounds
- Electrolytic extraction of reactive metals
- Aluminium production and electrode replacement
- Predicting Products in Aqueous Electrolysis
- Products at the Cathode and Anode
- Understanding Electrode Reactions in Electrolysis
- Writing Half Equations for Electrode Reactions
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Frequently asked questions
What is Topic C3: Chemical reactions?
Topic C3: Chemical reactions covers Introducing chemical reactions, Energetics, Types of chemical reactions, and Electrolysis in GCSE OCR Higher Combined Science Chemistry. 46 lessons in 4 subtopics.
What is the concentration formula?
The concentration formula is concentration = mass of solute ÷ volume of solution, measured in g/dm³. The Calculating Mass of Solute in Solutions notes cover this in full.
What is the law of conservation of mass?
The law of conservation of mass states that no atoms are lost or made during a chemical reaction, so the mass of the products equals the mass of the reactants. The The Law of Conservation of Mass notes cover this in full.
What is a base in chemistry?
A base is a substance that neutralises acids by accepting hydrogen ions. The Neutralisation Reactions and Salt Formulae notes cover this in full.
What is electrolysis?
Electrolysis is using an electric current to break down an ionic compound that is molten or dissolved. The Understanding Electrolytes and Ion Movement notes cover this in full.
How do you calculate percentage uncertainty?
Percentage uncertainty = uncertainty ÷ measured value × 100. The Understanding Uncertainty in Chemical Measurements notes cover this in full.
What is the order of the metal reactivity series?
The metal reactivity series, from most reactive to least reactive, is potassium, sodium, lithium, calcium, magnesium, aluminium, zinc, iron, copper. The Metal Reactions and the Reactivity Series notes cover this in full.
What is the test for hydrogen?
The test for hydrogen is to hold a burning splint at the mouth of the test tube: if hydrogen is present, it burns rapidly with a pop sound. The Testing for hydrogen gas notes cover this in full.
What are examples of endothermic reactions?
Examples of endothermic reactions include thermal decomposition, such as calcium carbonate breaking down into calcium oxide and carbon dioxide, and citric acid reacting with sodium hydrogencarbonate. The Examples and Applications of Energy Transfer Reactions notes cover this in full.