1. Air is a mixture of various gases. One of the gases is 21% part of the air and is essential for the survival of human beings. This gas is (a) nitrogen (b) oxygen (c) ozone argon
ScienceClass 8CBSEAnswered 28 Mar 2026
Answer
- Soln:
Answer is (b) oxygen
Explanation:
Nitrogen-78.09% Ozone-0.000004%
Argon- 0.93%
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