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Chemistry Revision

Atoms, reactions & the periodic table — part of Science on KODO.

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Chemistry is a core area of Science in the national curriculum. It covers essential concepts that build the foundation for GCSE study and beyond.

This topic includes subtopics such as Atoms, elements and compounds, States of matter and particle model, Acids and alkalis (pH), Chemical reactions and more. Each area is tested with multiple-choice questions that include detailed explanations to deepen your understanding.

Quick Reference

pH < 7Acidic
pH = 7Neutral
pH > 7Alkaline
First 10 elementsH, He, Li, Be, B, C, N, O, F, Ne

Key Definitions

Element
A substance made of only one type of atom. Listed on the periodic table.
Compound
A substance made of two or more different elements chemically bonded together.
Mixture
Two or more substances not chemically bonded — can be separated by physical methods.
Atom
The smallest particle of an element that retains its chemical properties.
pH scale
Measures acidity/alkalinity from 0 (strong acid) to 14 (strong alkali). 7 is neutral.

What You'll Cover

Atoms, elements and compounds
States of matter and particle model
Acids and alkalis (pH)
Chemical reactions
The Periodic Table
Periodic table
Acids, alkalis and pH
States of matter

Test Yourself — Chemistry

Try 3 quick questions. No account needed.

Quick Quiz

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Memory Tricks & Mnemonics

"OIL RIG" — Oxidation Is Loss, Reduction Is Gain (of electrons)

Remember redox reactions.

"Acid + Metal → Salt + Hydrogen"

Key reaction equation pattern.

"Acid + Alkali → Salt + Water" (neutralisation)

The most common reaction type in KS3 Chemistry.

Frequently Asked Questions

What is Atoms, elements and compounds in Science Chemistry?+
Atoms, elements and compounds is a key subtopic within Chemistry in Science. It's covered in the KS3 curriculum and tested in assessments. KODO provides multiple-choice questions with detailed explanations to help you master this area.
What is States of matter and particle model in Science Chemistry?+
States of matter and particle model is a key subtopic within Chemistry in Science. It's covered in the KS3 curriculum and tested in assessments. KODO provides multiple-choice questions with detailed explanations to help you master this area.
What is Acids and alkalis (pH) in Science Chemistry?+
Acids and alkalis (pH) is a key subtopic within Chemistry in Science. It's covered in the KS3 curriculum and tested in assessments. KODO provides multiple-choice questions with detailed explanations to help you master this area.
What is Chemical reactions in Science Chemistry?+
Chemical reactions is a key subtopic within Chemistry in Science. It's covered in the KS3 curriculum and tested in assessments. KODO provides multiple-choice questions with detailed explanations to help you master this area.
What is The Periodic Table in Science Chemistry?+
The Periodic Table is a key subtopic within Chemistry in Science. It's covered in the KS3 curriculum and tested in assessments. KODO provides multiple-choice questions with detailed explanations to help you master this area.
How many Chemistry questions does KODO have?+
KODO's Chemistry question bank is AI-powered and continuously expanding. Questions are multiple-choice with four options and include detailed explanations for every answer.
Is Chemistry revision on KODO free?+
Yes! KODO offers free daily quiz sessions for all topics including Chemistry. Revision cards are completely free with no limits. Pro users get unlimited quizzes and additional features.

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