2.1.5
Redox
Section 2.1.5 covers the rules for oxidation numbers in elements, compounds and ions, writing formulae from oxidation numbers and using Roman numerals, oxidation and reduction as electron transfer and as changes in oxidation number, the redox reactions of metals with acids, and interpreting unfamiliar redox equations. Disproportionation is revision support here and is examined in 3.1.3 for chlorine.
Revision Notes
Work through 2.1.5 Redox in a structured sequence.
Numbers
Oxidation Numbers
Oxidation numbers: the rules, calculating them in compounds, ions, peroxides and metal hydrides, Roman numerals and writing formulae.
Start revisingTransfer
Electron Transfer and Half-Equations
Redox as electron transfer: oxidising and reducing agents, oxidation number changes, writing ionic half-equations and combining them into full ionic equations.
Start revisingtionation
Disproportionation
Disproportionation: recognising it with oxidation numbers, chlorine in water and alkali, hydrogen peroxide, copper(I) and which species cannot disproportionate.
Start revisingClassification
Redox Classification
Classifying reactions with oxidation numbers: redox or not, s-block and p-block examples, metals with acids, and unfamiliar equations.
Start revising2.1.5 Redox – OCR A Level Chemistry A
The following OCR A learning outcomes state what candidates should be able to do. Wording is taken from the OCR A Level Chemistry A (H432) specification.
2.1.5 Redox
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