If the partial pressure of oxygen in air above a high altitu

If the partial pressure of oxygen in air above a high altitude lake is approximately 45 mm Hg, what would you predict to be the partial pressure of oxygen dissolved in the water at the surface of that lake?

A) 45 mm Hg

B) 95 mm Hg

C) 190 mm Hg

D) 3812 mm Hg

E) There is insufficient information provided to answer this question.

Solution

C) 190 mm Hg

The partial pressure of oxygen in the depth/lake is four times greater than the partial pressure at the surface. Given that the partial pressure at the surface is 45 mmHg, so, in the lake it would be approximately 180 mmHg.