The colsed ring compounds formed by bidentate ligands on binding to a metal or metal ions are called .

Options

A. MoNodentate
B. Chelates
C. Ambidentate
D. None of these

Answer

To solve the question regarding the closed ring compounds formed by bidentate ligands when they bind to a metal or metal ion, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Ligands**:
- Ligands are ions or molecules that can donate a pair of electrons to a metal ion to form a coordination complex.

2. **Types of Ligands**:
- Ligands can be classified based on the number of donor atoms they possess.
- **Monodentate ligands**: These ligands have one donor atom (e.g., Cl⁻, NH₃).
- **Bidentate ligands**: These ligands have two donor atoms that can bind to a metal ion (e.g., ethylene diamine).

3. **Formation of Closed Ring Compounds**:
- When a bidentate ligand binds to a metal ion, it can form a closed ring structure. This occurs because both donor atoms of the bidentate ligand coordinate to the metal ion, creating a cyclic structure.

4. **Terminology**:
- The closed ring compounds formed by bidentate ligands are specifically referred to as **chelate complexes**.
- The term "chelate" comes from the Greek word "chele," meaning claw, as the ligand "claws" around the metal ion.

5. **Conclusion**:
- Therefore, the correct answer to the question is that the closed ring compounds formed by bidentate ligands on binding to a metal or metal ions are called **chelate**.

### Final Answer:
- The closed ring compounds formed by bidentate ligands on binding to a metal or metal ions are called **chelate**.

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