In Mond's process following chemcial changes occurs:
`underset(("Impure"))(Ni)+CO overset(330-350K)(rarr)[P]`
`[P] overset (450-470K)(rarr) underset(("Pure")) (Ni)+CO`
Coordination number of `Ni` in `[P]` is…...

Explanation

To solve the problem regarding the coordination number of nickel (Ni) in the intermediate product [P] of Mond's process, we need to analyze the chemical changes that occur during this process.

### Step-by-Step Solution:

1. **Understanding Mond's Process**:
- Mond's process is a method for extracting nickel from its ores. It involves the formation of nickel carbonyl (Ni(CO)4) as an intermediate product.
- The reaction can be summarized as:
- Impure nickel (Ni) reacts with carbon monoxide (CO) at a temperature of 330-350 K to form nickel carbonyl (Ni(CO)4).
- This nickel carbonyl is then heated at 450-470 K to decompose back into pure nickel and carbon monoxide.

2. **Identifying the Intermediate Product**:
- The intermediate product [P] in the reactions is nickel carbonyl, which has the formula Ni(CO)4.

3. **Determining the Coordination Number**:
- The coordination number of a metal in a complex is defined as the number of ligand atoms that are bonded to the central metal atom.
- In nickel carbonyl (Ni(CO)4), the nickel atom is coordinated to four carbon monoxide (CO) ligands.

4. **Conclusion**:
- Since there are four CO ligands bonded to the nickel atom in Ni(CO)4, the coordination number of nickel in the intermediate product [P] is 4.

### Final Answer:
The coordination number of Ni in [P] (Ni(CO)4) is **4**.