The Type of isomerism present in pentaammine nitro chromium(III) perchlorate is .

Options

A. Optical
B. Linkage
C. Hydrate
D. Polymerisation

Explanation

To determine the type of isomerism present in pentaammine nitro chromium(III) perchlorate, we can follow these steps:

### Step 1: Identify the components of the complex
The complex is pentaammine nitro chromium(III) perchlorate. Here:
- The central metal ion is chromium (Cr).
- There are five ammonia (NH3) ligands, which are neutral.
- There is one nitro (NO2) ligand, which can act as a bidentate ligand (can donate from either nitrogen or oxygen).
- The counter ion is perchlorate (ClO4^-).

### Step 2: Write the formula of the complex
The formula of the complex can be written as:
\[ \text{[Cr(NH}_3\text{)}_5\text{NO}_2]^{3+} \text{ClO}_4^- \]
This indicates that the chromium ion is in the +3 oxidation state.

### Step 3: Analyze the ligands for isomerism
The nitro ligand (NO2) is ambidentate, meaning it can coordinate to the metal through either the nitrogen atom (N) or the oxygen atom (O). This property is crucial for determining the type of isomerism.

### Step 4: Determine the type of isomerism
Since the nitro ligand can bind through two different atoms, it leads to the formation of two different linkage isomers:
1. When the nitrogen atom is the donor: \[ \text{[Cr(NH}_3\text{)}_5\text{NO}_2]^{3+} \]
2. When the oxygen atom is the donor: \[ \text{[Cr(NH}_3\text{)}_5\text{ONO}]^{3+} \]

These two forms have the same molecular formula but differ in the connectivity of the ligands to the metal center.

### Step 5: Conclusion
The type of isomerism present in pentaammine nitro chromium(III) perchlorate is **linkage isomerism**.

### Final Answer
The type of isomerism present in pentaammine nitro chromium(III) perchlorate is **linkage isomerism**.

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