27 public questions tagged with this topic.
The coordination number is the number of ligand donor atoms directly bonded to the central metal ion. In [Co(NH₃)6]Cl₃, there are 6 NH₃ ligands, each unidentate, so the coordination number is 6.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Werner's Theory and Definitions - Ligands Coordination Number
In [Co(NH₃)4Cl₂]Cl, the Cl− outside the coordination sphere is ionizable. The 2 Cl− inside are ligands and not ionizable. Thus, 1 Cl− ionizes.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Werner's Theory and Definitions - Ligands Coordination Number
Primary valence is the oxidation state. In [CoCl₂(NH₃)4]Cl, the complex [CoCl₂(NH₃)4]+ has a +1 charge (balanced by 1 Cl−). NH₃ is neutral, Cl− is −1. Thus, Co’s oxidation state = +3 (since +3 + 2(−1) = +1).
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Werner's Theory and Definitions - Ligands Coordination Number
In [Co(H₂O)4Cl₂]Cl, the 1 Cl− outside the coordination sphere is ionizable and forms AgCl, while the 2 inside are ligands. Thus, 1 mole precipitates.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Werner's Theory and Definitions - Ligands Coordination Number
In [CoCl(NH₃)5]Cl₂, the two Cl− ions outside the coordination sphere are ionizable and precipitate as AgCl. The Cl inside is bonded to Co and does not precipitate. Thus, 2 moles of AgCl form.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Werner's Theory and Definitions - Ligands Coordination Number
Ligands are named alphabetically: ammine (NH₃), aqua (H₂O), chlorido (Cl). There are 4 NH₃, 1 H₂O, and 1 Cl in the complex. Co’s oxidation state is +3 (since [Co(NH₃)4(H₂O)Cl]2+ balances 2 Cl−). Name: tetraammineaquachloridocobalt(III) chloride.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Nomenclature of Coordination Compounds
Ligands: ammine (NH₃), aqua (H₂O), chlorido (Cl), alphabetically ordered. Co is +3 (balancing 3 Cl−). Name: diamminediaquadichloridocobalt(III) chloride.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Nomenclature of Coordination Compounds
[Cr(NH₃)6][Co(CN)6] swaps NH₃ and CN− between Co and Cr, showing coordination isomerism.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
These differ by the binding atom of NO₂− (N in nitro vs. O in nitrito), exhibiting linkage isomerism.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
Co₃+ (d6) in [CoF₆]3− (octahedral) with weak field F− is high spin: t2g4 eg2, giving 4 unpaired electrons.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
Each ligand (NH₃ and Cl−) donates 2 electrons. 5 NH₃ + 1 Cl− = 6 ligands, so 6 × 2 = 12 electrons.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
SCN− is ambidentate, binding via S or N.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Isomerism - Optical Isomerism and Linkage Ionisation Solvate
