Estimate the activity coefficient of oxygen in the following solutions at 298 K:
(a) 0.01 M NaCl;
(b) seawater
(c) wastewater containing 0.001 M Na2SO4 and 0.001 M CaSO4. Use the McDevit-Long equation from the text. ? = 0.0025. Oxygen solubility in pure water is 8.4 mg/P at 298 K and 1 atm total pressure.