Xe is a ..... ligand.

Options

A. ambidentate
B. bidentate
C. unidentate
D. hexadentate

Answer

**Step-by-Step Solution:**

1. **Understanding Ligands:**
- A ligand is defined as an atom, ion, or molecule that donates a pair of electrons to a metal atom or ion to form a coordination complex. Ligands can vary in their ability to donate electrons.

2. **Identifying Xenon (Xe):**
- Xenon is a noble gas and is generally considered to be chemically inert. However, it can form compounds under certain conditions, and in some cases, it can act as a ligand.

3. **Xenon as a Ligand:**
- In coordination chemistry, xenon can act as a ligand by donating a pair of electrons to a metal center. This was notably observed in the complex Au(Xe)4, where xenon acts as a ligand.

4. **Classification of Ligands:**
- Ligands are classified based on the number of donor atoms they possess:
- **Monodentate (Unidentate)**: Ligands that can donate one pair of electrons (one donor atom).
- **Bidentate**: Ligands that can donate two pairs of electrons (two donor atoms).
- **Polydentate**: Ligands that can donate multiple pairs of electrons (more than two donor atoms).

5. **Xenon as a Unidentate Ligand:**
- In the case of xenon, it donates only one pair of electrons to the metal center, which classifies it as a unidentate ligand.

6. **Conclusion:**
- Therefore, xenon (Xe) is classified as a **unidentate ligand**.

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