Chemistry A-Level
Chemistry A-Level glossary
7 key terms for Chemistry A-Level, A to Z, each linked to the topic pages that use it.
D
- Disproportionation
- A redox reaction in which the same element is both oxidised and reduced simultaneously.Pearson Edexcel
O
- Oxidation
- The loss of electrons from a substance, resulting in an increase in its oxidation number.Pearson Edexcel
- Oxidation Number
- A number assigned to an element in chemical combination that represents the number of electrons lost or gained by an atom of that element in the compound.Pearson Edexcel
- Oxidation Number (State)
- A number assigned to an element in chemical combination that represents the number of electrons lost or gained by an atom of that element in the compound.Pearson Edexcel
- Oxidising Agent
- A substance that accepts electrons from another substance, causing the other substance to be oxidised.Pearson Edexcel
R
- Reducing Agent
- A substance that donates electrons to another substance, causing the other substance to be reduced.Pearson Edexcel
- Reduction
- The gain of electrons by a substance, resulting in a decrease in its oxidation number.Pearson Edexcel
Where these terms come from
Each definition is one we publish on a Chemistry A-Level topic page or study guide. Open a term to see how each exam board words it and which topic it belongs to. For the full course, go to Chemistry revision or the glossary for every subject.
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