Question

Air contains about 21% oxygen by volume.

• A. True
• B. False

Answer 1

The correct option is A True

Air: The air in Earth’s atmosphere is made up of approximately 78 percent Nitrogen$\left({\mathrm{N}}_2\right)$ and 21 percent Oxygen$\left({\mathrm{O}}_2\right)$.

• Living things depend on the many different gases in the air.
• Air also has small amounts of other gases, too, such as Carbon dioxide$\left({\mathrm{CO}}_2\right)$, Neon$\left(\mathrm{Ne}\right)$, and Hydrogen$\left(\mathrm{H}\right)$.

Thus, the given statement is True i.e., air contains about 21% oxygen by volume.