Write true or false: `N_2 O_3` is known as laughing gas.

Explanation

To determine whether the statement "N₂O₃ is known as laughing gas" is true or false, we can follow these steps:

### Step 1: Identify the compound N₂O₃
- N₂O₃ is known as dinitrogen trioxide. It consists of two nitrogen atoms and three oxygen atoms.

### Step 2: Verify the common name for N₂O₃
- Dinitrogen trioxide (N₂O₃) is not commonly referred to as laughing gas.

### Step 3: Identify the correct compound known as laughing gas
- The compound that is commonly known as laughing gas is N₂O, which is nitrous oxide.

### Step 4: Conclusion
- Since N₂O₃ (dinitrogen trioxide) is not the same as nitrous oxide (N₂O), the statement "N₂O₃ is known as laughing gas" is false.

### Final Answer
The statement is **False**.

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