Question

Homoleptic complexes among the following are
(A) K₃[Al(C₂O₄)₃], (B) [CoCl₂(en)₂]⁺, (C) K₂[Zn(OH)₄]

• A. A only
• B. (A) and (B) only
• C. (A) and (C) only
• D. (C) only

Answer 1

The Correct Option is C

To solve the problem, we need to identify which of the given complexes are homoleptic. A homoleptic complex is defined as a coordination compound in which all the ligands are identical.

1. Understanding Homoleptic Complexes:
A homoleptic complex has only one type of ligand coordinated to the central metal ion. For example:
- $ \text{[Co(NH}_3\text{)}_6\text{]Cl}_3 $ is homoleptic because all ligands are $ \text{NH}_3 $.
- $ \text{[Co(NH}_3\text{)}_4\text{(H}_2\text{O)}_2\text{]}^{2+} $ is not homoleptic because it has two different ligands: $ \text{NH}_3 $ and $ \text{H}_2\text{O} $.

2. Analyzing Each Option:

(A) $ \text{K}_3\text{[Al(C}_2\text{O}_4\text{)}_3\text{]} $:
- The central metal ion is $ \text{Al}^{3+} $.
- The ligand is $ \text{C}_2\text{O}_4^{2-} $ (oxalate ion).
- All three ligands are identical ($ \text{C}_2\text{O}_4^{2-} $).
- Therefore, this is a homoleptic complex.

(B) $ \text{[CoCl}_2\text{(en)}_2\text{]}^+ $:
- The central metal ion is $ \text{Co}^{3+} $.
- The ligands are $ \text{Cl}^- $ and $ \text{en} $ (ethylenediamine, $ \text{H}_2\text{NCH}_2\text{CH}_2\text{NH}_2 $).
- There are two different types of ligands: $ \text{Cl}^- $ and $ \text{en} $.
- Therefore, this is not a homoleptic complex.

(C) $ \text{K}_2\text{[Zn(OH)}_4\text{]} $:
- The central metal ion is $ \text{Zn}^{2+} $.
- The ligand is $ \text{OH}^- $.
- All four ligands are identical ($ \text{OH}^- $).
- Therefore, this is a homoleptic complex.

3. Identifying the Correct Answer:
- From the analysis:
- Option (A) is homoleptic.
- Option (B) is not homoleptic.
- Option (C) is homoleptic.
- The correct answer includes options (A) and (C).

Final Answer:
The correct answer is $ \text{(A) and (C) only} $.

Answer 2

A homoleptic complex is a coordination compound that contains only one type of ligand. Now let's analyze each option:

• (A) K₃ [Al(C₂O₄)₃]: This is a homoleptic complex because it contains only oxalate ions (C₂O₄^2-) as ligands.
• (B) [CoCl₂(en)₂]⁺: This is not a homoleptic complex because it contains two different types of ligands: chloride ions (Cl^-) and ethylenediamine (en).
• (C) K₂ [Zn(OH)₄]: This is a homoleptic complex because it contains only hydroxide ions (OH^-) as ligands.

Thus, the homoleptic complexes are (A) and (C), making option (C) the correct answer.

The correct answer is (C) : (A) and (C) only.