Determination of Water Activity in Ammonium Sulfate and Sulfuric Acid Mixtures Using Levitated Single Particles

Water activities of ammonium sulfate-sulfuric acid mixtures with ammonium to sulfate molar ratios between 0 and 2 were measured by a spherical void electrodynamic levitator at relative humidities (RH) of 0.18–0.90. Since the composition of the solid particles is subject to uncertainty, solution properties were determined relative to the known properties at RH about 0.75–0.90. The data were compared with other measurements and the estimates from the Zdanovskii-Stokes-Robinson (ZSR) method and SCAPE, a newly developed gas-particle equilibrium model, and generally were found to be in good agreement.

[1]  J. Seinfeld,et al.  Atmospheric gas−aerosol equilibrium. II: Analysis of common approximations and activity coefficient calculation methods , 1993 .

[2]  J. Seinfeld,et al.  Atmospheric Gas-Aerosol Equilibrium I. Thermodynamic Model , 1993 .

[3]  J. Seinfeld,et al.  Coupling Thermodynamic Theory with Measurements to Characterize Acidity of Atmospheric Particles , 1993 .

[4]  J. Seinfeld,et al.  Water activities of NH4NO3/(NH4)2SO4 solutions , 1992 .

[5]  J. Seinfeld,et al.  Second-generation inorganic aerosol model , 1991 .

[6]  J. Seinfeld,et al.  Studies of concentrated electrolyte solutions using the electrodynamic balance. 1. Water activities for single-electrolyte solutions , 1987 .

[7]  J. Seinfeld,et al.  Continued development of a general equilibrium model for inorganic multicomponent atmospheric aerosols , 1987 .

[8]  I. Tang,et al.  Water activity measurements with single suspended droplets: The NaCl-H2O and KCl-H2O systems☆ , 1986 .

[9]  K. Pitzer.  Theoretical considerations of solubility with emphasis on mixed aqueous electrolytes , 1986 .

[10]  J. Seinfeld,et al.  A comparative study of equilibrium approaches to the chemical characterization of secondary aerosols , 1986 .

[11]  J. Spann,et al.  Measurement of the water cycle in mixed ammonium acid sulfate particles , 1985 .

[12]  C. B. Richardson,et al.  A novel isopiestic measurement of water activity in concentrated and supersaturated lithium halide solutions , 1984 .

[13]  I. Tang,et al.  An investigation of solute nucleation in levitated solution droplets , 1984 .

[14]  J. Seinfeld,et al.  Atmospheric equilibrium model of sulfate and nitrate aerosols—II. Particle size analysis , 1984 .

[15]  J. Spann,et al.  Measurement of the water cycle in a levitated ammonium sulfate particle , 1984 .

[16]  J. Seinfeld,et al.  Atmospheric equilibrium model of sulfate and nitrate aerosols , 1983 .

[17]  G. Habermehl,et al.  ReviewPure appl. Chem: Rinehart, K. L., et al. Marine natural products as sources of antiviral, antimicrobial, and antineoplastic Agents. 53, 795 (1981). (K. L. Rinehart, University of Illinois, Urbana, IL 61801, U.S.A.) , 1983 .

[18]  B. R. Staples.  Activity and osmotic coefficients of aqueous sulfuric acid at 298.15 K , 1981 .

[19]  J. Seinfeld,et al.  Chemical mass accounting of urban aerosol. , 1981, Environmental science & technology.

[20]  P. Saxena,et al.  Thermodynamics of multicomponent electrolytic aerosols , 1981 .

[21]  G. Rubel.  Measurement of the condensational growth of single hygroscopic acid aerosol droplets , 1981 .

[22]  I. Tang,et al.  Aerosol growth studies — IV. Phase transformation of mixed salt aerosols in a moist atmosphere , 1978 .

[23]  I. Tang,et al.  Aerosol growth studies—III ammonium bisulfate aerosols in a moist atmosphere , 1977 .

[24]  K. Pitzer,et al.  Thermodynamics of electrolytes. 7. Sulfuric acid , 1977 .

[25]  Kenneth S. Pitzer,et al.  Thermodynamics of electrolytes. IV. Activity and osmotic coefficients for mixed electrolytes , 1974 .

[26]  L. A. Bromley.  Thermodynamic properties of strong electrolytes in aqueous solutions , 1973 .

[27]  C. L. Kusik,et al.  Activity coefficients of strong electrolytes in multicomponent aqueous solutions , 1972 .

[28]  R. Robinson,et al.  Interactions in Aqueous Nonelectrolyte Solutions. I. Solute-Solvent Equilibria , 1966 .

[29]  K. Denbigh,et al.  The Principles of Chemical Equilibrium , 1956 .