The oxidation of `CHCl_(3)` by air & light is prevented by adding -

Options

A. `CH_(3)COOH`
B. `C_(2)H_(5)OH`
C. `CH_(3)CHO`
D. `CH_(3)COOCH_(3)`

Answer

To solve the question regarding the prevention of oxidation of CHCl₃ (chloroform) by air and light, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Chloroform and Its Oxidation**:
- Chloroform (CHCl₃) can undergo oxidation when exposed to air and light. This reaction can lead to the formation of harmful substances, particularly phosgene (COCl₂), which is toxic.

**Hint**: Recall the chemical structure of chloroform and the potential products of its oxidation.

2. **Identifying the Need for Prevention**:
- Due to the formation of phosgene, it is crucial to prevent the oxidation of chloroform. This is typically done during storage.

**Hint**: Consider the conditions under which chloroform is usually stored to avoid oxidation.

3. **Common Practices for Storage**:
- Chloroform is often stored in dark bottles to protect it from light, as UV light can catalyze the oxidation process.

**Hint**: Think about how light affects chemical reactions and why dark storage might be necessary.

4. **Adding Inhibitors**:
- To further prevent oxidation, substances known as inhibitors are added. In the case of chloroform, alcohol is commonly used.

**Hint**: Recall what types of substances are typically used as inhibitors in chemical reactions.

5. **Choosing the Right Alcohol**:
- Ethanol (C₂H₅OH) is the specific alcohol that is added to chloroform to inhibit oxidation. It reacts with phosgene to form harmless diethyl carbonate.

**Hint**: Consider the properties of different alcohols and their effectiveness in preventing oxidation.

6. **Conclusion**:
- Therefore, the correct answer to the question is that the oxidation of CHCl₃ by air and light is prevented by adding ethanol.

**Final Answer**: Ethanol (C₂H₅OH).