Carboxylic acids are reduced by red P and HI to

Options

A. alkanes
B. alcohols
C. alkenes
D. aldehydes.

Answer

To solve the question regarding the reduction of carboxylic acids by red phosphorus and HI, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**: The reactants in this reaction are carboxylic acids (RCOOH) and the reducing agent, which is red phosphorus (P) in the presence of hydroiodic acid (HI).

2. **Understand the Reaction**: Red phosphorus and HI act as a reducing agent. In organic chemistry, reducing agents are substances that can donate electrons or reduce the oxidation state of another substance. Here, they will reduce the carboxylic acid group (-COOH).

3. **Reduction Process**: The carboxylic acid (RCOOH) is reduced to an alkane (RCH3). The reduction involves the removal of the carboxyl group and the addition of hydrogen atoms. The general reaction can be represented as:
\[ RCOOH \xrightarrow{\text{Red P, HI}} RCH3 \]

4. **Final Product**: The final product of this reduction reaction is an alkane (RCH3). This means that the carboxylic acid is transformed into an alkane.

5. **Select the Correct Option**: Given the options (which are not specified in the question), the correct answer would be the one that indicates the formation of an alkane from the carboxylic acid.

### Conclusion:
Carboxylic acids are reduced by red phosphorus and HI to form alkanes.

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