In organic reactions , metallic lithium in liquid ammonia behaves as

Options

A. oxidising agent
B. reducing agent
C. bleaching agent
D. dehydrating agnet

Explanation

**Step-by-Step Solution:**

1. **Identify the Components**: The question involves metallic lithium (Li) and liquid ammonia (NH₃).

2. **Understand the Reaction Environment**: In organic chemistry, metallic lithium in liquid ammonia is often used in specific types of reactions, particularly in reductions.

3. **Determine the Role of Lithium**: Metallic lithium acts as a reducing agent. It donates electrons to other substances, facilitating their reduction.

4. **Identify the Type of Reduction**: The combination of lithium and liquid ammonia is known for a specific type of reduction called "Birch reduction". This process typically converts alkynes or aromatic compounds into trans-alkenes.

5. **Example Reaction**: For instance, if we take 1-butyne (C₄H₆), the reaction with lithium in liquid ammonia will yield trans-2-butene (C₄H₈) as the product.

6. **Conclusion**: Therefore, in organic reactions, metallic lithium in liquid ammonia behaves as a reducing agent, specifically facilitating the Birch reduction that leads to the formation of trans products.

**Final Answer**: In organic reactions, metallic lithium in liquid ammonia behaves as a reducing agent.

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