`CoCl_(2) + KNO_(2) + CH_(3)COOH to [X] +H_(2)O +KCl + CH_(3)COOK +NO`
(Unbalenced equation)

Options

A. `X` is a yellow crystalline solid insoluble in water.
B. `X` is a green coloured compounds known as kinman's green
C. `IUPAC` name of `X` is potassium hexanitrito-`N`-cobaltate (II)
D. The compound `X` is an inner orbital complex.

Explanation

To solve the given reaction \( \text{CoCl}_2 + \text{KNO}_2 + \text{CH}_3\text{COOH} \rightarrow [X] + \text{H}_2\text{O} + \text{KCl} + \text{CH}_3\text{COOK} + \text{NO} \), we need to identify the compound \( [X] \) formed in the reaction.

### Step-by-Step Solution:

1. **Identify Reactants and Products**:
- The reactants are Cobalt(II) chloride (\( \text{CoCl}_2 \)), Potassium nitrite (\( \text{KNO}_2 \)), and Acetic acid (\( \text{CH}_3\text{COOH} \)).
- The products include \( [X] \), water (\( \text{H}_2\text{O} \)), Potassium chloride (\( \text{KCl} \)), Potassium acetate (\( \text{CH}_3\text{COOK} \)), and Nitric oxide (\( \text{NO} \)).

2. **Determine the Nature of Compound \( [X] \)**:
- The reaction involves the formation of a coordination complex. Cobalt(II) ions can form complexes with nitrite ions.
- The presence of \( \text{KNO}_2 \) suggests that the nitrite ion acts as a ligand.

3. **Write the Formula for the Complex**:
- The complex formed is \( \text{K}_3[\text{Co}(\text{NO}_2)_6] \).
- This complex is known as Potassium hexanitrocobaltate(II).

4. **Identify the Color and Solubility**:
- The complex \( \text{K}_3[\text{Co}(\text{NO}_2)_6] \) is a yellow crystalline solid and is insoluble in water.

5. **Determine the IUPAC Name**:
- The IUPAC name for the complex is Potassium hexanitrocobaltate(II).

6. **Final Conclusion**:
- Therefore, the compound \( [X] \) is \( \text{K}_3[\text{Co}(\text{NO}_2)_6] \), which is a yellow crystalline solid and an inner orbital complex.

### Final Answer:
- The answer is \( [X] = \text{K}_3[\text{Co}(\text{NO}_2)_6] \) (Potassium hexanitrocobaltate(II)), which is a yellow crystalline solid and an inner orbital complex.