Question

Amount of $C{O}_2$ in expired air is about

• A. $0.03\%$
• B. $21\%$
• C. $0.04\%$
• D. $4.5\%$

Answer 1

The correct option is D $4.5\%$

Amount of $C{O}_2$

• Expired air contains 100 times more $C{O}_2$ than inspired air, as $C{O}_2$ formed as waste during respiration, is released from the body.
• Inspired air contains $0.03\%$ $C{O}_2$
• Expired air has $4.5\%$ $C{O}_2$

Final answer :
(D) $4.5\%$