The treatment of ethene with cold alkaline potassium permanganate produces,

Options

A. ethylene glycol
B. formaldehyde
C. formic acid
D. carbon dioxide and water

Explanation

To solve the question regarding the treatment of ethene with cold alkaline potassium permanganate, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactant in this case is ethene, which has the chemical formula \( \text{C}_2\text{H}_4 \) or \( \text{CH}_2=CH_2 \).
- The other reactant is cold alkaline potassium permanganate, represented as \( \text{KMnO}_4 \) in a basic solution.

2. **Understand the Reaction Conditions**:
- The term "cold" indicates that the reaction occurs at room temperature (around 298-303 K).
- "Alkaline" means that the reaction takes place in a basic medium, which is typically achieved by adding a small amount of sodium hydroxide or potassium hydroxide to the potassium permanganate solution.

3. **Identify the Type of Reaction**:
- Potassium permanganate (\( \text{KMnO}_4 \)) acts as an oxidizing agent in this reaction.
- In the presence of cold alkaline conditions, it oxidizes alkenes to form diols.

4. **Determine the Product**:
- When ethene is treated with cold alkaline potassium permanganate, it undergoes syn-dihydroxylation, resulting in the formation of a 1,2-diol.
- Specifically, the product formed is ethylene glycol, which can be represented as \( \text{C}_2\text{H}_6\text{O}_2 \) or \( \text{HO-CH}_2-CH_2-\text{OH} \).

5. **Conclusion**:
- Therefore, the treatment of ethene with cold alkaline potassium permanganate produces ethylene glycol.

### Final Answer:
The treatment of ethene with cold alkaline potassium permanganate produces **ethylene glycol**.

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