Which is most difficult to oxidise-

Options

A. HCHO
B. `CH_(3)`CHO
C. `CH_(3)"COCH"_(3)`
D. `CH_(3) CH_(2)`CHO

Answer

To determine which compound is the most difficult to oxidize among the given options, we will analyze the oxidation behavior of each compound step by step.

### Step 1: Identify the Compounds
We are comparing three compounds:
1. HCHO (Formaldehyde)
2. CH3CHO (Acetaldehyde)
3. CH3C(=O)CH3 (Acetone)

### Step 2: Understand Oxidation of Each Compound
- **Formaldehyde (HCHO)**: This compound is an aldehyde and is easily oxidized to formic acid (HCOOH) using both mild and strong oxidizing agents. Therefore, it is not difficult to oxidize.

- **Acetaldehyde (CH3CHO)**: Similar to formaldehyde, acetaldehyde is also an aldehyde. It can be oxidized to acetic acid (CH3COOH) relatively easily. Thus, it is also not difficult to oxidize.

- **Acetone (CH3C(=O)CH3)**: Acetone is a ketone. The oxidation of ketones is generally more challenging compared to aldehydes. When attempting to oxidize acetone using strong oxidizing agents like KMnO4, it does not oxidize easily. This is because oxidizing acetone would require breaking the carbon skeleton, which is a more complex process.

### Step 3: Conclusion
Based on the analysis, acetone is the most difficult compound to oxidize among the three options provided.

### Final Answer
The most difficult compound to oxidize is **Acetone (CH3C(=O)CH3)**.

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