1% pure ethyl alcohol is added to the chloroform used in hospitals because:

Options

A. It enhances the oxidation of chloroform
B. The poisonous gas phosgene is not formed
C. Ethyl alcohol converts phosgene into into diethyl carbonate non-toxic salt
D. It is helpful in producing unconsciousness

Answer

To answer the question of why 1% pure ethyl alcohol is added to chloroform used in hospitals, we can break down the reasoning into several steps:

### Step-by-Step Solution:

1. **Identify the Chemical Composition of Chloroform**:
- Chloroform is chemically represented as CHCl₃.

2. **Understand the Risks of Chloroform**:
- Chloroform can decompose when exposed to sunlight and oxygen, leading to the formation of a toxic compound known as phosgene (COCl₂).

3. **Recognize the Formation of Phosgene**:
- The reaction can be summarized as:
\[ \text{CHCl}_3 + \frac{1}{2} \text{O}_2 \xrightarrow{\text{sunlight}} \text{COCl}_2 + \text{other products} \]
- Phosgene is a poisonous gas and poses health risks.

4. **Role of Ethyl Alcohol**:
- Ethyl alcohol (C₂H₅OH) is added to chloroform to prevent the formation of phosgene. When ethyl alcohol is present, it reacts with any formed phosgene to produce diethyl carbonate, which is a non-toxic compound.

5. **Chemical Reaction Involving Ethyl Alcohol**:
- The reaction can be represented as:
\[ \text{COCl}_2 + 2 \text{C}_2\text{H}_5\text{OH} \rightarrow \text{(C}_2\text{H}_5\text{O)}_2\text{CO} + 2 \text{HCl} \]
- This reaction shows that ethyl alcohol effectively converts the harmful phosgene into a harmless substance.

6. **Conclusion**:
- The primary reason for adding 1% pure ethyl alcohol to chloroform is to prevent the formation of the toxic gas phosgene and to convert it into diethyl carbonate, which is non-toxic.

### Final Answer:
1% pure ethyl alcohol is added to chloroform used in hospitals to convert any phosgene formed into diethyl carbonate, a non-toxic compound.

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