Which of the following pairs show coordination isomerism?

Options

A. `[Co(NH_(3))_(6)][Cr(CN)_(6)] and [Cr(NH_(3))_(6)][Co(CN)_(6)]`
B. `[Co(NH_(3))_(3)(H_(2)O)_(2)Cl]Br_(2) and [Co(NH_(3))_(3)(H_(2)O)Cl*Br]Br*H_(2)O`
C. `[Pt(NH_(3))_(4)Cl_(2)]Br_(2) and [Pt(NH_(3))_(3)B_(2)]Cl_(2)`
D. `[Co(NH_(3))_(3)(CN)_(3)][Co(NH_(3))_(3)(CN)_(3)]`

Explanation

To determine which pairs show coordination isomerism, we need to understand the definition of coordination isomers. Coordination isomers are compounds that have the same formula but differ in the distribution of ligands between the cationic and anionic parts of the compound.

Let's analyze the provided pairs step by step:

### Step 1: Identify the Ligands and Central Metal Atoms
- For each pair, identify the ligands (molecules or ions that are coordinated to the central metal) and the central metal atoms.

### Step 2: Check for Cationic and Anionic Species
- Determine if the compounds in each pair consist of both cationic and anionic species. Coordination isomerism requires the presence of both types of species.

### Step 3: Analyze Ligand Distribution
- For the pairs that have both cationic and anionic species, check if the ligands are distributed differently between the cationic and anionic parts.

### Step 4: Conclusion
- Based on the analysis, conclude which pairs exhibit coordination isomerism.

### Example Analysis
1. **First Pair**: Cobalt with amine ligands and chromium with cyano ligands.
- This pair shows coordination isomerism because the ligands are interchanged between the cationic and anionic parts.

2. **Second Pair**: Contains amine but lacks distinct cationic and anionic species.
- This pair does not show coordination isomerism.

3. **Third Pair**: Contains different ions but lacks the distribution of ligands in cationic and anionic species.
- This pair does not show coordination isomerism.

4. **Fourth Pair**: Both parts have the same ligands and central metal.
- This pair does not show coordination isomerism.

### Final Answer
- The only pair that shows coordination isomerism is the **first pair**.