Which of the following complexes are homoleptic ?

Options

A. `[Co(NH_(3))_(6)]^(3+)`
B. `[Co(NH_(3))_(4)Cl_(2)]^(+)`
C. `[Ni(CN)_(4)]^(2-)`
D. `[Ni(NH_(3))_(4) Cl_(2)]`

Explanation

To determine which of the given complexes are homoleptic, we need to follow these steps:

### Step 1: Understand the Definition of Homoleptic Complexes
Homoleptic complexes are defined as coordination compounds that contain only one type of ligand. This means that all the ligands attached to the central metal atom or ion are identical.

**Hint:** Remember that "homo" means "same", so look for complexes with only one kind of ligand.

### Step 2: Analyze Each Option
We will examine each of the provided options to see if they contain only one type of ligand.

1. **Option 1: Cobalt with Ammonia (Co(NH₃)₆)**
- In this complex, cobalt is coordinated only with ammonia ligands. There are no other types of ligands present.
- **Conclusion:** This is a homoleptic complex.

2. **Option 2: Cobalt with Ammonia and Chlorine (Co(NH₃)₄Cl₂)**
- This complex contains two different types of ligands: ammonia and chlorine.
- **Conclusion:** This is not a homoleptic complex.

3. **Option 3: Nickel with Cyanide (Ni(CN)₄)**
- Here, nickel is coordinated only with cyanide ligands. There are no other types of ligands present.
- **Conclusion:** This is a homoleptic complex.

4. **Option 4: Cobalt with Ammonia and Chlorine (Co(NH₃)₂Cl₄)**
- Similar to option 2, this complex contains both ammonia and chlorine ligands.
- **Conclusion:** This is not a homoleptic complex.

### Step 3: Finalize the Answer
Based on the analysis:
- **Homoleptic complexes identified:**
- Option 1: Co(NH₃)₆ (only ammonia)
- Option 3: Ni(CN)₄ (only cyanide)

Thus, the homoleptic complexes are **Option 1 and Option 3**.

**Final Answer:** The homoleptic complexes are **Option 1 and Option 3**.