Chloroform by reacting with conc. HNO3 produces:

Options

A. Water gas
B. Laughing gas
C. Tear gas
D. Producer gas

Answer

To determine the product formed when chloroform (CHCl3) reacts with concentrated nitric acid (HNO3), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactants are chloroform (CHCl3) and concentrated nitric acid (HNO3).

2. **Understand the Reaction**:
- Chloroform is a haloalkane, and concentrated nitric acid is a strong oxidizing agent. When they react, the hydrogen atom in chloroform can be substituted by a nitro group (NO2).

3. **Write the Reaction**:
- The reaction can be represented as:
\[ \text{CHCl}_3 + \text{HNO}_3 \rightarrow \text{CCl}_3\text{NO}_2 + \text{HCl} + \text{H}_2\text{O} \]
- Here, one hydrogen atom from chloroform is replaced by a nitro group, resulting in the formation of chloropicrin (CCl3NO2), also known as nitrochloroform.

4. **Identify the Product**:
- The product formed is chloropicrin (CCl3NO2), which is also referred to as nitrochloroform.

5. **Classify the Product**:
- Chloropicrin is known to be a tear gas, which is used in various applications including as a chemical warfare agent.

6. **Conclusion**:
- Therefore, the product formed when chloroform reacts with concentrated HNO3 is chloropicrin, commonly known as tear gas.

### Final Answer:
Chloroform reacts with concentrated HNO3 to produce chloropicrin (CCl3NO2), which is also known as tear gas.

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