A : dien is bidentate ligand.
R : dien donates two pairs of electron 

Options

A. Both Assertion & Reason are true and the reason is the correct explanation of the assertion
B. Both Assertion & Reason are true but the reason is not the correct explanation of the assertion
C. Assertion is true statement but Reason is false
D. Both Assertion and Reason are false statements

Answer

To solve the question, we need to analyze the assertion and the reason provided in the context of coordination chemistry.

### Step-by-Step Solution:

1. **Understanding the Assertion:**
- The assertion states that "dien is a bidentate ligand."
- "dien" refers to diethylene triamine, which has the formula NH2CH2CH2NHCH2CH2NH2.
- A bidentate ligand is defined as a ligand that can donate two pairs of electrons to a central metal atom.

2. **Analyzing the Structure of dien:**
- Diethylene triamine contains three nitrogen atoms, each of which has a lone pair of electrons.
- This means that dien can potentially donate three pairs of electrons, making it a tridentate ligand rather than a bidentate ligand.

3. **Understanding the Reason:**
- The reason states that "dien donates two pairs of electrons."
- Since dien has three nitrogen atoms, it can donate three pairs of electrons, not just two.

4. **Conclusion:**
- The assertion that "dien is a bidentate ligand" is incorrect because it is actually a tridentate ligand.
- The reason that "dien donates two pairs of electrons" is also incorrect because it can donate three pairs of electrons.
- Therefore, both the assertion and the reason are false.

### Final Answer:
Both assertion and reason are false statements.

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