When propionic acid is subjected to reduction with hydroiodic acid acid Red phosphorus ,the product formed is

Options

A. Butane
B. Propane
C. Ethane
D. None of these

Answer

To solve the question regarding the reduction of propionic acid with hydroiodic acid and red phosphorus, we can follow these steps:

### Step 1: Identify the Structure of Propionic Acid
Propionic acid has the chemical formula \( \text{C}_3\text{H}_6\text{O}_2 \) or \( \text{CH}_3\text{CH}_2\text{COOH} \). It consists of a three-carbon chain with a carboxylic acid functional group.

### Step 2: Write the Reaction for Reduction
When propionic acid is treated with hydroiodic acid (\( \text{HI} \)) in the presence of red phosphorus, a reduction reaction occurs. The general reaction can be represented as:
\[ \text{CH}_3\text{CH}_2\text{COOH} + 6 \text{HI} \xrightarrow{\text{Red P}} \text{CH}_3\text{CH}_2\text{CH}_3 + 2 \text{H}_2\text{O} + 3 \text{I}_2 \]

### Step 3: Determine the Product
From the reaction, we can see that the propionic acid is reduced to propane (\( \text{C}_3\text{H}_8 \) or \( \text{CH}_3\text{CH}_2\text{CH}_3 \)). The reduction process involves the removal of the carboxylic acid group and the addition of hydrogen atoms, resulting in the formation of an alkane.

### Step 4: Conclusion
The product formed from the reduction of propionic acid with hydroiodic acid and red phosphorus is propane.

### Final Answer
Thus, the correct answer to the question is **propane**.

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