Question

A mixture of helium, nitrogen and oxygen has a total pressure of 821 mmHg. The partial pressure of helium is 105 mmHg, and the partial pressure of nitrogen is 312 mmHg. What is the partial pressure (in mmHg) of oxygen in the mixture?

Answer 1

Total partial pressure, Pt = 821 mm Hg

Partial pressure of Helium, P1 = 105 mm Hg

Partial pressure of Nitrogen, P2 = 312 mm Hg

Partial pressure of Oxygen, P3 = ? mm Hg

According to Dalton's law of Partial pressures,

Pt = P1 + P2 + P3

So, P3 = 404 mm Hg