Question

Air is a mixture of various gases. One of the gas is 21% part of the air and is essential for the survival of human beings. This gas is ______.

Options

• nitrogen

• oxygen

• ozone

• argon

Answer 1

Air is a mixture of various gases. One of the gas is 21% part of the air and is essential for the survival of human beings. This gas is oxygen.

Explanation:

Oxygen makes up about 21% of air by volume. It is essential for the survival of human beings.