What volume of oxygen will be present in 150 cm^3 of air at 20^0 C?

What volume of oxygen will be present in 150 cm^3 of air at 20^0 C?

A. 21 cm^3

B. 31.5 cm^3

C. 117 cm^3

D. 1.5 cm^3

Air contains about 21% oxygen by volume.

Calculation:

Volume of oxygen = {21}/{100} * 150  cm^3

= 31.5  cm^3

✅ Correct Answer:

B. 31.5 cm³

(Temperature given does not affect the percentage composition since air and oxygen expand equally.)

PQN: 10