What is the Partial Pressure of Oxygen in Air at Sea

Question

What is the partial pressure of oxygen in air at sea level?
A) 400 mm Hg
B) 160 mm Hg
C) 60 mm Hg
D) 600 mm Hg
E) 210 mm Hg

Accepted Answer

The partial pressure of oxygen in air at sea level is approximately 160 mm Hg. This is calculated using the fact that oxygen makes up about 21% of air, and the total atmospheric pressure at sea level is about 760 mm Hg. $0.21 \times 760 \approx 160$ mm Hg.