The comlexes `[Co(NH_3)_6] [Cr(CN)_6] and [Cr(NH_3)_6] [Co(CN)_6]` are the examples of which type of isomerism?

Options

A. Geometrical isomerism
B. Linkage isomerism
C. Ionisation isomerism
D. Coordination isomerism

Explanation

To determine the type of isomerism exhibited by the complexes \([Co(NH_3)_6][Cr(CN)_6]\) and \([Cr(NH_3)_6][Co(CN)_6]\), we can follow these steps:

### Step 1: Identify the Complexes
The given complexes are:
- \([Co(NH_3)_6][Cr(CN)_6]\) - This is a cationic complex with cobalt as the cation and chromium complexed with cyanide as the anion.
- \([Cr(NH_3)_6][Co(CN)_6]\) - This is an anionic complex with chromium as the cation and cobalt complexed with cyanide as the anion.

### Step 2: Understand the Nature of the Complexes
In these complexes, we have:
- A cationic part: \([Co(NH_3)_6]^{3+}\) and \([Cr(NH_3)_6]^{3+}\)
- An anionic part: \([Cr(CN)_6]^{3-}\) and \([Co(CN)_6]^{3-}\)

### Step 3: Analyze the Ligands
In both complexes, the ligands are interchanged:
- In the first complex, cobalt is coordinated with ammonia ligands, while chromium is coordinated with cyanide ligands.
- In the second complex, chromium is coordinated with ammonia ligands, while cobalt is coordinated with cyanide ligands.

### Step 4: Determine the Type of Isomerism
Since the cationic and anionic parts of the complexes have exchanged their ligands, this is a classic example of coordination isomerism. Coordination isomerism occurs when the ligands around the central metal ions are rearranged between the cationic and anionic parts of the complex.

### Conclusion
The complexes \([Co(NH_3)_6][Cr(CN)_6]\) and \([Cr(NH_3)_6][Co(CN)_6]\) exhibit **coordination isomerism**.

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