A haloalkane can be reduced to an alkane with the help of HI in presence of red phosphorus. Red phosphorus

Options

A. acts as reducing agent
B. acts as dehydrating agent
C. is used to regenerate HI
D. acts as a catalyst

Answer

To solve the question about the role of red phosphorus in the reduction of haloalkanes to alkanes using HI, let's break it down step by step.

### Step-by-Step Solution:

1. **Understanding the Reaction**:
- A haloalkane (alkyl halide) can be reduced to an alkane. The reducing agent in this reaction is hydroiodic acid (HI), and red phosphorus is used as a catalyst to facilitate the reaction.

2. **Role of Red Phosphorus**:
- Red phosphorus acts as a reducing agent in this reaction. It helps in the generation of iodine from HI, which is crucial for the reduction process. The presence of red phosphorus enhances the reactivity of HI.

3. **Mechanism of Reduction**:
- The mechanism involves the nucleophilic attack of iodide ions (I-) generated from HI on the carbon atom of the haloalkane. This leads to the substitution of the halogen atom (X) with hydrogen, resulting in the formation of an alkane.

4. **Final Product**:
- The final product of this reduction reaction is an alkane, which is formed after the halogen atom is replaced by a hydrogen atom.

5. **Conclusion**:
- Therefore, the role of red phosphorus in the reaction is to act as a catalyst that facilitates the reduction of haloalkanes to alkanes using hydroiodic acid.

### Answer:
Red phosphorus acts as a reducing agent in the presence of HI to convert haloalkanes to alkanes.

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