Substances burn more readily in `N_(2)O` than in air because `N_(2)O`:

Options

A. is reactive at high temperature
B. dissociates to give more oxygen than in air.
C. the activation energy is increased on increasing temperature
D. acts as a catalyst

Answer

To solve the question "Substances burn more readily in N₂O than in air because N₂O:", we need to analyze the options provided and understand the role of oxygen in combustion.

### Step-by-Step Solution:

1. **Understanding Combustion**:
- Combustion is a chemical reaction that typically requires a fuel and an oxidizer (usually oxygen). The more oxygen available, the more readily a substance can burn.

2. **Analyzing N₂O**:
- N₂O, or nitrous oxide, is a compound that contains nitrogen and oxygen. Its chemical structure allows it to release oxygen when it decomposes.

3. **Comparing Oxygen Content**:
- Air contains approximately 21% oxygen. In contrast, when N₂O decomposes, it can release more oxygen.
- The decomposition reaction of N₂O can be represented as:
\[ 2N_2O \rightarrow 2N_2 + O_2 \]
- This shows that from 2 moles of N₂O, 1 mole of O₂ is produced.

4. **Calculating Oxygen Percentage in N₂O**:
- The molar mass of N₂O is approximately 44 g/mol (28 g/mol from N and 16 g/mol from O).
- The oxygen contribution from N₂O can be calculated as:
\[ \text{Percentage of Oxygen in N₂O} = \frac{\text{mass of O}}{\text{total mass}} \times 100 = \frac{16}{44} \times 100 \approx 36.36\% \]
- This indicates that N₂O has a higher percentage of oxygen compared to air.

5. **Conclusion**:
- Since N₂O can provide more oxygen than air, substances will burn more readily in N₂O. Therefore, the correct answer is:
- **Option B: N₂O dissociates to give more oxygen than air.**