The solubility of oxygen in lakes high in the Rocky Mountains is affected by the altitude. If the aqueous solubility of atmospheric O₂ is 2.67 × 10^-4 M at sea level and 25°C,what is the solubility of O₂ at an elevation of 12,000 ft where the total pressure is 0.657 atm? Assume the temperature is 25°C,and that the mole fraction of O₂ in air is 0.209
At both 12,000 ft and at sea level.

Question

Quizplus · Accepted Answer

The solubility of a gas is directly proportional to its partial pressure (Henry's Law). At 12,000 ft, the partial pressure of O₂ is 0.657 atm × 0.209 = 0.137 atm. The solubility at sea level is 2.67 × 10⁻⁴ M with a partial pressure of 0.209 atm. Therefore, the solubility at 12,000 ft is (0.137/0.209) × 2.67 × 10⁻⁴ M = 1.75 × 10⁻⁴ M.

The Solubility of Oxygen in Lakes High in the Rocky