What this topic covers
Topic 4: Chemical changes has 3 subtopics:
- Reactivity of metals
- Reactions of acids
- Electrolysis
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GCSE AQA Higher Combined Science Chemistry · Topic 4 of 11
Topic 4: Chemical changes – GCSE AQA Higher Combined Science Chemistry revision notes
Choose a subtopic. Topic 4: Chemical changes covers Reactivity of metals, Reactions of acids, and Electrolysis in GCSE AQA Higher Combined Science Chemistry. 24 lessons in 3 subtopics.
Revise Topic 4: Chemical changes for GCSE AQA Higher Combined Science Chemistry, including Reactivity of metals, Reactions of acids, and Electrolysis.
24
Lessons
3
Subtopics
Topic 4: Chemical changes lessons by subtopic
24 lessons, grouped by subtopic.
Reactivity of metals
- Metal Reactions and the Reactivity Series
- Displacement Reactions and the Extended Reactivity Series
- How metals are found and extracted
- Reduction and oxidation in metal extraction
- Evaluating metal extraction processes
- Understanding Oxidation and Reduction with Electrons
- Writing Ionic Equations for Displacement Reactions
- Metal Oxides and Oxidation Reactions
Reactions of acids
- What Salts Are Produced in Neutralisation?
- Neutralisation Reactions and Salt Formulae
- Making Soluble Salts from Acids
- Crystallising Salt Solutions and Making Pure Samples
- Acid-Metal Reactions: Products and Patterns
- Redox in Acid-Metal Reactions
- Understanding Acid Strength and Concentration
- pH Scale and Hydrogen Ion Concentration
Electrolysis
- Understanding Electrode Reactions in Electrolysis
- Writing Half Equations for Electrode Reactions
- Predicting Products in Aqueous Electrolysis
- Products at the Cathode and Anode
- Electrolytic extraction of reactive metals
- Aluminium production and electrode replacement
- Products of Electrolysis in Molten Ionic Compounds
- Understanding Electrolytes and Ion Movement
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Frequently asked questions
What is Topic 4: Chemical changes?
Topic 4: Chemical changes covers Reactivity of metals, Reactions of acids, and Electrolysis in GCSE AQA Higher Combined Science Chemistry. 24 lessons in 3 subtopics.
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.
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 an alkali?
An alkali is a soluble base that releases hydroxide ions (OH⁻) when dissolved in water. The Neutralisation Reactions and Salt Formulae notes cover this in full.
What is a displacement reaction?
A displacement reaction is a reaction where a more reactive element takes the place of a less reactive element in a compound. The Displacement Reactions and the Extended Reactivity Series notes cover this in full.
What is a redox reaction?
A redox reaction is one in which oxidation and reduction both occur. The Understanding Oxidation and Reduction with Electrons notes cover this in full.
What is an electrolyte?
An electrolyte is a liquid or solution that conducts electricity because it contains free-moving ions. The Understanding Electrolytes and Ion Movement notes cover this in full.
What is rust?
Rust is iron oxide, formed when iron slowly oxidises in damp air. The Metal Oxides and Oxidation Reactions notes cover this in full.