Chemistry A-Level
Oxidation number rules
What Oxidation number rules means in Chemistry A-Level, as defined for OCR.
Definition of Oxidation number rules
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Reference: OCR
An uncombined element has oxidation number 0, a monatomic ion has its charge, oxygen is usually −2 and hydrogen usually +1 in compounds.
Topics that use Oxidation number rules
- Redox (OCR A-Level)
Related terms
- Calculating an unknown value from known contributions
- Deducing formulae from stated oxidation numbers
- Disproportionation
- Distinguishing compounds of the same element
- Electron transfer
- Half-equations
- Ordered rules for assigning oxidation numbers
- Oxidation
Using Oxidation number rules in the exam
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