The Solubility of Elemental Mercury Vapor in Water

Abstract The solubility of mercury vapor in water has been measured by means of atomic absorption spectrophotometry over the temperature range of 5–60°C under atmospheric pressure. The aqueous solubility obeys Henry’s law at each temperature. The solubilities and the Henry coefficients are reported. From the solubility data, the heat of the solution of mercury vapor in water is found to be −5.3 kcal/mol. The relationship between the Henry coefficient, k, and the solution temperature, T, is expressed by logk=−1078×1⁄T+6.250. From this equation, the solubilities at 70–100°C are estimated. The solubility of the mercury vapor in sea water has also been measured over the temperature range of 5–30°C. A salting-out effect on the solubility is observed. The practical application of the aqueous solubility of the mercury vapor is discussed from the analytical point of view.