What does the Acids, metals and energy module cover?

This module gathers the acids, metals and energy content of Chemistry 2 in WJEC GCSE Science Double Award. It covers acids, bases and alkalis and the pH scale, the reactions of acids with metals, bases and carbonates and preparing soluble salts, the reactivity series and displacement, the extraction of metals by carbon or electrolysis, the electrolysis of molten compounds and aluminium, and exothermic and endothermic reactions with reaction profiles.

Which unit and paper assess this module?

These topics are part of Unit 5 (Chemistry 2), a written paper of 1 hour 15 minutes worth 15 percent of the Double Award qualification, sat at Foundation or Higher tier. Questions mix recall, the salt-preparation and energy practicals, and explanation.

What practical skills are needed here?

You need to use indicators and the pH scale, prepare a pure soluble salt (excess base, filter, evaporate, crystallise), carry out displacement reactions, predict the products of electrolysis, and measure the temperature change of a reaction to classify it as exothermic or endothermic.

What kinds of question come up?

Expect questions on the pH scale and neutralisation, the general reactions of acids and naming salts, the reactivity series and displacement, why metals are extracted by carbon or electrolysis, the products of electrolysis and the extraction of aluminium, and exothermic and endothermic reactions with reaction profiles and activation energy.

How should I revise this module?

Learn the pH scale, indicators and neutralisation, and the three reactions of acids with their salts. Learn the reactivity series, displacement, and the carbon-versus-electrolysis rule for extraction. Understand electrolysis and the products at each electrode, and exothermic/endothermic reactions with reaction profiles. Use WJEC Double Award past papers and watch the command words.

WalesCombined Science

WJEC GCSE Science Double Award: Acids, metals and energy (Unit 5, Chemistry 2) overview

An overview of the Acids, metals and energy module in WJEC GCSE Science Double Award (Unit 5, Chemistry 2), mapping acids, bases and the pH scale, the reactions of acids and preparing salts, the reactivity series and extraction, electrolysis, and energy changes in reactions.

Generated by Claude Opus 4.86 min readDouble Award Unit 5 (Chemistry 2)Updated 2026-06-15

Reviewed by: AI editorial process; not yet individually human-reviewed

Jump to a section

The topics in this module
How this module fits the exam
How to study this module

The Acids, metals and energy module gathers the acids, metals and energy content of Chemistry 2 in WJEC GCSE Science Double Award. It covers how acids react, how metals are arranged by reactivity and extracted, and the energy changes in reactions. This page maps the module and links to a focused answer page for each part.

The topics in this module

Acids, bases and the pH scale: Acids, bases and alkalis, the pH scale and indicators, and neutralisation. See Acids, bases and the pH scale.
Reactions of acids and preparing salts: The reactions of acids and how to prepare a soluble salt. See Reactions of acids and preparing salts.
The reactivity series and extraction: The reactivity series, displacement, and extracting metals. See The reactivity series and extraction.
Electrolysis: Breaking down ionic compounds with electricity and extracting aluminium. See Electrolysis.
Energy changes and reactions: Exothermic and endothermic reactions and reaction profiles. See Energy changes and reactions.

How this module fits the exam

These topics sit in Unit 5 (Chemistry 2), a written paper of 1 hour 15 minutes worth 15%. Questions mix recall (pH, reactivity series), practicals (salt preparation, energy change) and explanation (extraction, electrolysis).

How to study this module

Learn the pH scale and neutralisation. Indicators, the acid/alkali regions, and salt + water.
Know the reactions of acids. With metals, bases and carbonates, and naming salts.
Master the reactivity series. Displacement and the carbon-versus-electrolysis rule.
Understand electrolysis. The products at each electrode and aluminium extraction.
Learn energy changes. Exothermic and endothermic, reaction profiles and activation energy.

Then test yourself with the module quiz.

Sources & how we know this

WJEC GCSE Science (Double Award) specification (from 2016) — WJEC (2016)