The Henry’s law constant for O2 in water at 25°C is 1.27×10−3M/atm and the mole fraction of O2 in the atmosphere is 0.21. Calculate the solubility of O2 in water at 25°C at an atmospheric pressure of 1.00 atm.Strategy: ▪ Use Dalton’s law of partial pressures to calculate the partial pressure of oxygen.▪ Use Henry’s law to calculate the solubility, expressed as the concentration of dissolved gas.

• A. 2.5×10-4 M
• B. 2.1×10-4 M
• C. 2.3×10-4 M
• D. 2.7×10-4M