Which of the following does not give yellow solid on treatment with sodium hypoiodite?

Options

A. Pentan-3-one
B. Pentan-2-one
C. Acetophenone
D. Ethanal

Explanation

To solve the question, "Which of the following does not give yellow solid on treatment with sodium hypoiodite?", we need to identify which of the given compounds does not undergo the haloform reaction. The haloform reaction is characterized by the formation of iodoform (CHI3), which is a yellow solid, when a compound of the form R-CO-CH3 is treated with sodium hypoiodite (NaOH-I2).

### Step-by-Step Solution:

1. **Understand the Haloform Reaction**:
- The haloform reaction occurs with compounds that have the structure R-CO-CH3 (where R can be any alkyl group). This reaction leads to the formation of iodoform (CHI3), which is a yellow solid.

2. **Identify the Compounds**:
- Let's analyze the given options:
1. Pentane-3-one (C5H10O)
2. Pentane-2-one (C5H10O)
3. Acetophenone (C8H8O)
4. Ethanol (C2H6O)

3. **Check Each Compound**:
- **Pentane-3-one**: Structure is CH3-CH2-C(=O)-CH2-CH3. This does not have the CO-CH3 structure, so it will not give a yellow solid.
- **Pentane-2-one**: Structure is CH3-C(=O)-CH2-CH2-CH3. This has the CO-CH3 structure, so it will give a yellow solid.
- **Acetophenone**: Structure is C6H5-C(=O)-CH3. This also has the CO-CH3 structure, so it will give a yellow solid.
- **Ethanol**: Structure is CH3-CH2-OH. This does not have the CO-CH3 structure, so it will not give a yellow solid.

4. **Conclusion**:
- From the analysis, Pentane-3-one and Ethanol do not give a yellow solid on treatment with sodium hypoiodite. However, since the question asks for a single option, and based on the context of the video, the correct answer is **Pentane-3-one**.

### Final Answer:
**Pentane-3-one does not give yellow solid on treatment with sodium hypoiodite.**