Nitrogen is used to fill electric bulb because:

Options

A. it is lighter then air
B. it makes the bulb glow
C. it is non toxic
D. it does not support combustion

Explanation

**Step-by-Step Text Solution:**

1. **Understanding the Composition of Nitrogen:**
Nitrogen is a diatomic molecule (N₂) that consists of two nitrogen atoms. The two nitrogen atoms are held together by a very strong triple bond.

2. **Properties of Nitrogen:**
Due to the presence of the strong triple bond, nitrogen is very stable and does not easily react with other substances. This stability is crucial for its use in electric bulbs.

3. **Inert Nature of Nitrogen:**
Nitrogen is classified as an inert gas because it does not readily participate in chemical reactions. This property is essential in preventing reactions that could lead to the degradation of the bulb's components.

4. **Role of Nitrogen in Electric Bulbs:**
When an electric bulb is lit, the filament inside gets very hot and can react with oxygen in the air, leading to oxidation and burning out of the filament. By filling the bulb with nitrogen, which does not support combustion, the filament is protected from oxidation.

5. **Conclusion:**
Therefore, nitrogen is used to fill electric bulbs primarily because it creates an inert environment that prevents the filament from reacting with oxygen, thus prolonging the life of the bulb.

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