Question

The most abundant element in the earth's atmosphere is:

• A. Nitrogen
• B. Sulphur
• C. Hydrogen
• D. Oxygen

Hint:

Atmosphere composition: N2 (78%), O2 (21%), Ar (0.93%), CO2 (0.04%).
Nitrogen is essential for plant growth (N2 fixation).

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
This question tests knowledge of atmospheric composition.

Step 2: Detailed Explanation:
The Earth's atmosphere is composed of:
- Nitrogen (N2): About 78.08% (most abundant).
- Oxygen (O2): About 20.95%.
- Argon (Ar): About 0.93%.
- Carbon dioxide (CO2): About 0.04%.
- Other gases in trace amounts.
Other elements:
- Sulphur (B): Present in trace amounts.
- Hydrogen (C): Present in trace amounts (water vapour).
- Oxygen (D): Second most abundant.
Thus, nitrogen is the most abundant element in the Earth's atmosphere.

Step 3: Final Answer:
Thus, the most abundant element in the Earth's atmosphere is nitrogen.
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