Specification Point 2.20:
Understand the terms: Oxidation, Reduction, Redox, Oxidising Agent, Reducing Agent in terms of gain or loss of Oxygen and loss or gain of electrons


Oxidation & Reduction table

Oxidation state: The applied valancy (number of electrons lost/gained) of an element in a compound is called an oxidation state.

e.g.: Oxidation state of carbon (C) in carbon monoxide (CO) is +2.

Oxidation of carbon (C) in carbon dioxide (CO2) is +4.

P.S: The total oxidation of a compound is 0

CO = 0
C + (-2) = 0
C -2 = 0
C = +2

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Author: Jamie

Jamie got a First class degree in Chemistry from Oxford University before going on to teach chemistry full time as a professional tutor. He’s put together these handy revision notes to match the Edexcel IGCSE Chemistry specification so you can learn exactly what you need to know for your exams.