What does The Earth and its resources module cover?

This module gathers the water, atmosphere and limestone content of Chemistry 1 in WJEC GCSE Science Double Award. It covers the stages of water treatment and testing purity, solubility and saturated solutions, the composition and evolution of the atmosphere, the greenhouse effect and climate change, the products and pollutants of burning fuels, and the limestone cycle and its uses.

Which unit and paper assess this module?

These topics are part of Unit 2 (Chemistry 1), 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, data interpretation and explanation.

What practical and data skills are needed here?

You need to describe the water treatment stages and the test for water purity, read and use solubility curves, and interpret data on atmospheric gases and rising carbon dioxide. You should also know the test for carbon dioxide (limewater turning cloudy) and the reactions of the limestone cycle.

What kinds of question come up?

Expect questions on the stages of water treatment, saturated solutions and solubility, the composition and evolution of the atmosphere, the greenhouse effect and human causes of climate change, complete and incomplete combustion and the pollutants from fuels, and the limestone cycle with the uses of quicklime and slaked lime.

How should I revise this module?

Learn the water treatment stages and why each matters, and the meaning of solubility and a saturated solution. Memorise the atmospheric proportions and how the atmosphere evolved, and the greenhouse effect with the pollutants from fuels. Learn the limestone cycle reactions and the uses of limestone and lime. Use WJEC Double Award past papers and watch the command words.

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WJEC GCSE Science Double Award: The Earth and its resources (Unit 2, Chemistry 1) overview

An overview of The Earth and its resources module in WJEC GCSE Science Double Award (Unit 2, Chemistry 1), mapping water treatment and solubility, the Earth's atmosphere and its evolution, climate change and air quality, and limestone and its uses.

Generated by Claude Opus 4.86 min readDouble Award Unit 2 (Chemistry 1)Updated 2026-06-15

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

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

The Earth and its resources module gathers the water, atmosphere and limestone content of Chemistry 1 in WJEC GCSE Science Double Award. It explains how we make water safe, how the atmosphere formed and is changing, and how a single rock provides many useful materials. This page maps the module and links to a focused answer page for each part.

The topics in this module

Water treatment and solubility: The stages of water treatment, testing purity, and solubility and saturated solutions. See Water treatment and solubility.
The Earth's atmosphere and its evolution: The composition of today's atmosphere and how it changed. See The Earth's atmosphere and its evolution.
Climate change and air quality: The greenhouse effect, human-caused climate change, and the pollutants from burning fuels. See Climate change and air quality.
Limestone and its uses: The limestone cycle and the uses of limestone, quicklime and slaked lime. See Limestone and its uses.

How this module fits the exam

These topics sit in Unit 2 (Chemistry 1), a written paper of 1 hour 15 minutes worth 15%. Questions mix recall (treatment stages, atmospheric gases), data interpretation (solubility curves, carbon dioxide trends) and explanation (the greenhouse effect, the limestone cycle).

How to study this module

Learn the water treatment stages. Filtration, sedimentation, filtration and chlorination, and why each is needed.
Understand solubility. Saturated solutions and how temperature affects solubility.
Know the atmosphere. The proportions today and how it evolved through the oceans and photosynthesis.
Explain climate change. The greenhouse effect, the human causes, and the pollutants from fuels.
Master the limestone cycle. The reactions and the uses of limestone and lime.

Then test yourself with the module quiz.

Sources & how we know this

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