Which decolourises the colour of acidic `KMnO_(4)`

Options

A. `CH_(3)COOH`
B. `CH_(3)CH_(2)COOH`
C. `COOH.COOH`
D. `CH_(3)COOC_(2)H_(5)`

Explanation

To determine which compound decolorizes the color of acidic KMnO₄, we need to analyze the options provided and their reactivity with potassium permanganate (KMnO₄), which is a strong oxidizing agent.

### Step-by-Step Solution:

1. **Understanding the Reactivity of KMnO₄**:
- KMnO₄ in acidic medium is known to oxidize various organic compounds, particularly those containing double bonds (alkenes, alkynes) and certain functional groups like alcohols and aldehydes.

2. **Analyzing the Options**:
- Let's consider the possible compounds that could be listed as options. Common candidates might include:
- Acetic acid (CH₃COOH)
- Propanoic acid (CH₃CH₂COOH)
- Formic acid (HCOOH)
- Oxalic acid (C₂H₂O₄)
- Ethyl acetate (CH₃COOCH₂CH₃)

3. **Evaluating Each Compound**:
- **Acetic Acid (CH₃COOH)**: This compound does not have a double bond and will not react with KMnO₄ to decolorize it.
- **Propanoic Acid (CH₃CH₂COOH)**: This compound can be oxidized by KMnO₄, leading to decolorization.
- **Formic Acid (HCOOH)**: This is a strong reducing agent and can also reduce KMnO₄, resulting in decolorization.
- **Oxalic Acid (C₂H₂O₄)**: This compound can also reduce KMnO₄, leading to decolorization.
- **Ethyl Acetate (CH₃COOCH₂CH₃)**: This ester does not react with KMnO₄ and will not cause decolorization.

4. **Conclusion**:
- From the analysis, both Propanoic acid and Oxalic acid can decolorize KMnO₄. However, if we are to select one based on the context provided in the transcript, it indicates that the correct answer is **Oxalic Acid (C₂H₂O₄)**.

### Final Answer:
Oxalic acid (C₂H₂O₄) decolorizes the color of acidic KMnO₄.