Ethyl alcohol is denatured by adding `:`

Options

A. Methanol and formic acid
B. KCN
C. `CH_(3) OH and C_(6) H_(6)`
D. `CH_(3) OH` and pyridine

Answer

To answer the question "Ethyl alcohol is denatured by adding:", we will follow these steps:

### Step-by-Step Solution:

1. **Understanding Denatured Alcohol**:
- Denatured alcohol refers to ethanol (ethyl alcohol) that has been treated with additives to make it unfit for human consumption. This is done to prevent recreational use and to discourage drinking of industrial alcohol.

2. **Common Additives**:
- The most common additives used to denature ethyl alcohol include methanol and pyridine. Methanol is added to make the alcohol poisonous, while pyridine is added to impart a bad taste and foul smell.

3. **Analyzing the Options**:
- Let's evaluate the options provided:
- **Option A**: Methanol and formic acid - Formic acid is not typically used for denaturing.
- **Option B**: KCN - Potassium cyanide is not used for denaturing alcohol.
- **Option C**: Methanol and C6H6 (benzene) - Benzene is not used for denaturing alcohol.
- **Option D**: Methanol and pyridine - This is a correct combination as both are commonly used for denaturing.

4. **Conclusion**:
- Based on the analysis, the correct answer is **Option D: Methanol and pyridine**. These additives serve the purpose of making the alcohol unpalatable and toxic.

### Final Answer:
Ethyl alcohol is denatured by adding **methanol and pyridine**.

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