Coordination number
What Coordination number means in Chemistry A-Level, as defined for OCR.
Definitions of Coordination number
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Reference: OCR
The number of ligands attached to the metal in a complex, such as six-coordinate with four ammonia and two water ligands.
The number of coordinate bonds from ligands to the central metal ion, so it counts donor atoms, not ligands.
The number of ligands bonded to the central ion, which changes only when that number changes.
Topics that use Coordination number
- Transition elements (OCR A-Level)
Related terms
- Balanced ionic equations for precipitation
- Balancing complex half-equations
- bidentate ligands
- Bidentate ligands giving octahedral complexes
- Bond angles and shape prediction
- Boundary cases scandium and zinc
- Calculating oxidation state from a formula
- Catalytic behaviour of transition metals and their compounds
Using Coordination number in the exam
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