What is the coordination number of metal in `[M("trien")("dipy")]^(pmn)`?

Explanation

To determine the coordination number of the metal in the complex \([M(\text{trien})(\text{dipy})]^{pmn}\), we need to analyze the ligands present and how many donor atoms they contribute to the coordination sphere of the metal.

### Step-by-Step Solution:

1. **Identify the Ligands**: The complex contains two ligands: trien (triethylenetetramine) and dipyridine (dipy).

2. **Analyze the Ligand trien**:
- Trien is a tetradentate ligand, meaning it can form four bonds with the central metal atom.
- This is because trien has four nitrogen atoms that can donate lone pairs to the metal.

3. **Analyze the Ligand dipy**:
- Dipy is a bidentate ligand, meaning it can form two bonds with the central metal atom.
- This is due to the two nitrogen atoms present in the dipyridine structure that can donate lone pairs.

4. **Calculate the Total Coordination Number**:
- From trien, we have 4 donor atoms.
- From dipy, we have 2 donor atoms.
- Therefore, the total coordination number is:
\[ \text{Total Coordination Number} = 4 (\text{from trien}) + 2 (\text{from dipy}) = 6 \]

5. **Conclusion**: The coordination number of the metal in the complex \([M(\text{trien})(\text{dipy})]^{pmn}\) is 6.