Coordination Compounds
Learn Coordination Compounds with notes, examples, and practice questions.
Chapter Overview
Coordination compounds have a central metal ion bonded to ligands. Werner's theory, nomenclature, isomerism, VBT, and CFT explain structure, colour, and magnetic behaviour.
Basics
Complex
[ML_n]^(charge) ; ligands L donate electron pairs
Coordination number
Number of donor atoms bonded to metal
Primary valence
Ionisable (Werner)
Secondary valence
Non-ionisable bonds to ligands
Nomenclature (IUPAC sketch)
- Ligands alphabetically before metal
- Anionic ligands end in -o (chloro, cyano)
- Cationic complex: metal as in complex
- Oxidation state in Roman numerals
Isomerism & Theories
- Structural: ionisation, linkage, coordination
- Stereoisomerism: geometrical (cis/trans), optical
- VBT: hybridisation predicts geometry
- CFT: splitting Δ_o explains colour and magnetism
Solved Examples
Step-by-step solutions — read each step before checking the final answer.
Name
[Co(NH₃)₆]Cl₃.
- 1Hexaamminecobalt(III) chloride
Answer
Hexaamminecobalt(III) chloride
CN
CN of [Fe(CN)₆]⁴⁻.
- 16 cyano ligands
Answer
6
Key Points to Remember
- ✓ Chelate: polydentate ligand ring
- ✓ Strong field: low spin; weak field: high spin
- ✓ EDTA tetradentate/hexadentate
Exam Tips
- • Name ligands before metal
- • Draw cis/trans for square planar and octahedral
- • Use CFT for colour/magnetic questions
Formula Cheat Sheet
Quick reference — NCERT board exam formulas
Coordination Chemistry
- Complex:[ML_n]^(charge) ; ligands donate electron pairs
- Coordination number:Number of donor atoms bonded to metal
- Primary valence:Ionisable (Werner)
- Secondary valence:Non-ionisable bonds to ligands
- Chelate: polydentate ligand forms ring with metal
- CFT: crystal field splitting Δ_o explains colour & magnetism
Practice MCQs — Coordination Compounds
Test your understanding with topic-wise multiple choice questions. Explanations appear after each answer.
Coordination number is: