Chemistry A-Level
4s and 3d energies
What 4s and 3d energies means in Chemistry A-Level, as defined for AQA.
Definition of 4s and 3d energies
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Reference: AQA
These sub-levels lie close in energy, so once 4s electrons are removed, 3d electrons can be lost without a large jump in ionisation energy.
Topics that use 4s and 3d energies
- Variable oxidation states (A-level only) (AQA A-Level)
Related terms
- combining half-equations
- deducing oxidation states
- colour sequence
- half-equations in acid
- reduction by zinc
- variable oxidation states
Using 4s and 3d energies in the exam
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