If 20% of the air is composed of O₂, the partial pressure of oxygen at an altitude of 20,000 feet where atmospheric pressure is 350 mm Hg is
A)20 mm Hg
B)760 mm Hg
C)70 mm Hg
D)350 mm Hg
E)152 mm Hg

Question

Quizplus · Accepted Answer

The partial pressure of oxygen at an altitude of 20,000 feet where atmospheric pressure is 350 mm Hg can be calculated using Dalton's law of partial pressures. According to this law, the total pressure of a mixture of gases is equal to the sum of the partial pressures of the individual gases in the mixture.

Given that 20% of the air is composed of oxygen, we can calculate the partial pressure of oxygen as follows:

Partial pressure of oxygen = 20% of atmospheric pressure
= 0.20 x 350 mm Hg
= 70 mm Hg

Therefore, the partial pressure of oxygen at an altitude of 20,000 feet where the atmospheric pressure is 350 mm Hg is 70 mm Hg, which is option C.

If 20% of the Air Is Composed of O₂, the Partial