Which of the following represents laughing gas

Options

A. NO
B. `N_2 O`
C. `NO_2`
D. `N_2 O_3`

Explanation

To determine which of the following represents laughing gas, we need to identify the chemical compound commonly known as laughing gas.

### Step-by-Step Solution:

1. **Identify the Options**: The question provides several chemical formulas: NO, N2O, and N2O3. We need to analyze these to find out which one is associated with laughing gas.

2. **Understanding Laughing Gas**: Laughing gas is a common name for a specific compound that induces laughter when inhaled. It is known for its anesthetic properties and is often used in dental procedures.

3. **Chemical Composition**:
- **NO**: This is nitrogen monoxide, which is not known as laughing gas.
- **N2O**: This is dinitrous oxide, which is indeed known as laughing gas.
- **N2O3**: This is dinitrogen trioxide, which is not associated with laughing gas.

4. **Conclusion**: Based on the analysis, the correct representation of laughing gas is **N2O**.

### Final Answer:
The chemical compound that represents laughing gas is **N2O**.

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