When glycerol is treated with a small amount of HI or `PI_(3)`, the product obtained is:

Options

A. Glycerol triiodide
B. Allyl iodide
C. 2-Iodopropane
D. None

Explanation

To solve the question regarding the treatment of glycerol with a small amount of HI or PI3, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Glycerol Structure**:
- Glycerol, also known as glycerin, has the molecular formula C3H8O3. Its structure can be represented as:
\[ \text{CH}_2\text{OH} - \text{CHOH} - \text{CH}_2\text{OH} \]
- It contains three hydroxyl (-OH) groups.

2. **Reaction with HI or PI3**:
- When glycerol is treated with hydrogen iodide (HI) or phosphorus triiodide (PI3), the hydroxyl groups can be converted into iodide groups.
- The reaction typically involves the substitution of the -OH groups with iodine (I).

3. **Formation of Iodinated Product**:
- In the presence of HI, each hydroxyl group in glycerol can be replaced by iodine, leading to the formation of 1,2,3-triiodopropane:
\[ \text{CH}_2\text{I} - \text{CHOH} - \text{CH}_2\text{I} \]
- However, this product is unstable and can undergo further reactions.

4. **Decomposition of Triiodopropane**:
- The triiodopropane can lose iodine to form an alkene. The intermediate can rearrange and lose iodine to form propene (CH3-CH=CH2).

5. **Final Product Formation**:
- The propene can then react with another molecule of HI, leading to the formation of 2-iodopropane:
\[ \text{CH}_3 - \text{CH(I)} - \text{CH}_3 \]
- Therefore, the final product obtained when glycerol is treated with a small amount of HI or PI3 is 2-iodopropane.

### Conclusion:
The product obtained when glycerol is treated with a small amount of HI or PI3 is **2-iodopropane**.

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