`[Pt("trien")]^(2+)` is a ……. Ligand on the basis of its denticity.

Explanation

To determine the denticity of the ligand `[Pt("trien")]^(2+)`, we need to analyze the structure of the ligand "trien," which stands for triethylenetetramine.

### Step-by-Step Solution:

1. **Identify the Ligand**: The ligand in question is triethylenetetramine (trien). It is a bidentate ligand, meaning it can form two bonds with a central metal atom.

2. **Understand the Structure**: Triethylenetetramine consists of three ethylene groups and one amine group. The structure can be visualized as having multiple nitrogen atoms that can donate lone pairs to the central metal.

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