Thermodynamics of B(OH)3 in the vapor phase of water: Vapor–liquid and Henry's constants, fugacity and second cross virial coefficients

Available experimental data are employed to determine: (1) the enthalpy of formation, ΔfH°, of B(OH)3, in the ideal gas state; (2) the value of the Krichevskii parameter, (∂P/∂x2)T,V,x2=0c for boric acid in water; (3) values of the vapor–liquid distribution constants and Henry's constants for H3BO3 at infinite dilution in water for temperatures between 273.15 K and Tc. The obtained information allows calculation of the fugacity coefficients for boric acid in the vapor phase of water and second cross virial coefficients for interactions between molecules of H2O and B(OH)3 at temperatures between 450 and Tc.

► Thermodynamics of H3BO3 in the vapor phase of water and in the ideal gas state.
► Vapor–liquid distribution and Henry's constants of H3BO3 in water are determined at temperatures between 273.15 and Tc.
► Negative values of ln ϕ2∞ for H3BO3 signal strong attractive interactions between boric acid and water at vapor densities.
► Calculated values of B12 are about 3.6 times the values of B11 at studied temperatures (450–620 K).