Question

2(iv) Name the gas which makes up about 78% of the atmosphere.

Answer 1

• Air is a mixture of gases.
• It is composed of 78% Nitrogen, 21% Oxygen, 1% Carbon dioxide, and a small number of other gases like Hydrogen, Helium, Argon, etc.
• Nitrogen is a major component of amino acids, building blocks of protein.

Final answer: Nitrogen