Which of the following complex has same oxidation state of the central metall atom in the cationic and anionic part ?

Options

A. `[Pt(Py)_4][PtCl_4]`
B. `[Pt(NH_3)_4][PtCl_6]`
C. `[Pt(NH_3)_4Cl_2][PtCl_4]`
D. In all the above

Answer

To solve the question, we need to determine the oxidation states of the central metal atom in both the cationic and anionic parts of the given complexes. We will analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding the Question**: We need to find a complex where the central metal atom has the same oxidation state in both the cationic and anionic parts.

2. **Analyzing Option A: [Pt(Py)4]²⁺ and [PtCl₄]²⁻**:
- The cationic part is [Pt(Py)₄]²⁺.
- Py (pyridine) is a neutral ligand, so it does not contribute to the charge.
- The overall charge of the cation is +2.
- Therefore, the oxidation state of Pt in [Pt(Py)₄]²⁺ is +2.
- The anionic part is [PtCl₄]²⁻.
- Cl (chloride) is a -1 charged ligand, and there are four Cl ligands.
- The total charge contributed by Cl is -4.
- To balance this and give an overall charge of -2, the oxidation state of Pt must be +2.
- **Conclusion for Option A**: The oxidation state of Pt in both parts is +2. Thus, this option satisfies the condition.

3. **Analyzing Option B: [Pt(NH₃)₄]²⁺ and [PtCl]**:
- The cationic part is [Pt(NH₃)₄]²⁺.
- NH₃ is a neutral ligand, so it does not contribute to the charge.
- The overall charge of the cation is +2.
- Therefore, the oxidation state of Pt in [Pt(NH₃)₄]²⁺ is +2.
- The anionic part is [PtCl].
- Cl is a -1 charged ligand.
- To balance this and give an overall charge of 0, the oxidation state of Pt must be +1.
- **Conclusion for Option B**: The oxidation states are +2 in the cation and +1 in the anion, which do not match.

4. **Final Conclusion**:
- After analyzing both options, we find that only Option A has the same oxidation state of the central metal atom in both the cationic and anionic parts.

### Answer:
The correct option is **A: [Pt(Py)₄]²⁺ and [PtCl₄]²⁻**.