Advertisement

Isopiestic Determination of the Osmotic and Activity Coefficients of the {yNaH2PO4 + (1 − y)KH2PO4}(aq) System at T = 298.15 K

  • Tijana Ivanović
  • Daniela Ž. Popović
  • Jelena Miladinović
  • Joseph A. Rard
  • Zoran P. Miladinović
  • Svetlana Belošević
  • Katarina Trivunac
Article
  • 11 Downloads

Abstract

Isopiestic measurements have been made for aqueous mixtures of NaH2PO4 and KH2PO4 at T = (298.15 ± 0.01) K, at NaH2PO4 ionic strength fractions y = (0, 0.19108, 0.38306, 0.58192, and 1), assuming that both electrolytes dissociate as 1:1 electrolytes, using KCl(aq) as the reference standard solution. Model parameters for an extended form of Pitzer’s ion-interaction model and also for the Clegg–Pitzer–Brimblecombe equations based on the mole-fraction-composition scale were evaluated at T = 298.15 K for NaH2PO4(aq) using the present isopiestic results (13 values), as were those for KH2PO4(aq) using the present isopiestic results (12 values), together with numerous critically-assessed osmotic coefficients for both electrolytes taken from the published literature. The thermodynamic models for KH2PO4(aq) extend to m = 2.187 mol·kg−1, which is slightly above saturation, while those for NaH2PO4(aq) extend to m = 7.5 mol·kg−1, which is below saturation. The 39 osmotic coefficients for the ternary mixtures from the present study along with 42 values from a published study were likewise represented with these models, with both the usual Pitzer mixing terms and also Scatchard’s neutral-electrolyte model mixing terms being used for the extended ion-interaction model. Two mixing parameters were needed for each of the models, and all three models gave similar quality representations of the experimental results. Maximum differences in calculated values of mean molality-based activity coefficients for these three models are ∆γ±(NaH2PO4) ≤ 0.0080 and ∆γ±(KH2PO4) ≤ 0.0043. The experimental results were also found to nearly conform to Zdanovskii’s rule.

Keywords

Aqueous solutions Isopiestic measurements NaH2PO4 KH2PO4 Osmotic coefficients Activity coefficients 

Notes

Acknowledgements

This work was supported by the Ministry for Science and Environmental Protection of the Republic of Serbia under Project No. 172063.

References

  1. 1.
    Cox, J.D., Wagman, D.D., Medvedev, V.A.: CODATA Key Values for Thermodynamics. Hemisphere, New York (1989)Google Scholar
  2. 2.
    Rard, J.A., Wolery, T.J.: The standard chemical-thermodynamic properties of phosphorus and some of its key compounds and aqueous species: an evaluation of differences between the previous recommendations of NBS/NIST and CODATA. J. Solution Chem. 36, 1585–1599 (2007)CrossRefGoogle Scholar
  3. 3.
    Popović, D.Ž., Miladinović, J., Todorović, M.D., Zrilić, M.M., Rard, J.A.: Isopiestic determination of the osmotic and activity coefficients of K2HPO4(aq), including saturated and supersaturated solutions, at T = 298.15 K. J. Solution Chem. 40, 907–920 (2011)CrossRefGoogle Scholar
  4. 4.
    Popović, D.Ž., Miladinović, J., Todorović, M.D., Zrilić, M.M., Rard, J.A.: Isopiestic determination of the osmotic and activity coefficients of the {yKCl + (1 – y)K2HPO4}(aq) system at T = 298.15 K. J Chem Thermodyn 43, 1877–1885 (2011)CrossRefGoogle Scholar
  5. 5.
    Popović, D.Ž., Miladinović, J., Miladinović, Z.P., Grujić, S.R., Todorović, M.D., Rard, J.A.: Isopiestic determination of the osmotic and activity coefficients of the {yKBr + (1 – y)K2HPO4}(aq) system at T = 298.15 K. J. Chem. Thermodyn. 62, 151–161 (2013)CrossRefGoogle Scholar
  6. 6.
    Popović, D.Ž., Miladinović, J., Miladinović, Z.P., Ivošević, B.B., Todorović, M.D., Rard, J.A.: Isopiestic determination of the osmotic and activity coefficients of the {yKNO3 + (1 – y)K2HPO4}(aq) system at T = 298.15 K. J. Chem. Thermodyn. 55, 172–183 (2012)CrossRefGoogle Scholar
  7. 7.
    Popović, D.Ž., Miladinović, J., Rard, J.A., Miladinović, Z.P., Grujić, S.R.: Isopiestic determination of the osmotic and activity coefficients of the {yK2SO4 + (1 – y)K2HPO4}(aq) system at T = 298.15 K. J. Chem. Thermodyn. 79, 84–93 (2014)CrossRefGoogle Scholar
  8. 8.
    Popović, D.Ž., Miladinović, J., Rard, J.A., Miladinović, Z.P., Grujić, S.R.: Isopiestic determination of the osmotic and activity coefficients of the {yNa2HPO4 + (1 – y)K2HPO4}(aq) system at T = 298.15 K. J. Solution Chem. 45, 1261–1287 (2016)CrossRefGoogle Scholar
  9. 9.
    Stokes, J.M.: The osmotic and activity coefficients of sodium and potassium dihydrogen phosphate at 25 °C. Trans. Faraday Soc. 41, 685–688 (1945)CrossRefGoogle Scholar
  10. 10.
    Scatchard, G., Breckenridge, R.C.: Isotonic solutions. II. The chemical potential of water in aqueous solutions of potassium and sodium phosphates and arsenates at 25°. J. Phys. Chem. 58, 596–602 (1954)CrossRefGoogle Scholar
  11. 11.
    Simanova, S.A., Shul’ts, M.M.: Thermodynamic study of the system KH2PO4–NH4H2PO4–H2O at 25°. Activity of water and activity coefficients of KH2PO4 and NH4H2PO4 in binary and ternary solutions (in Russian). Vestn. Leningr. Univ., Fiz. Khim. 3, 82–89 (1966)Google Scholar
  12. 12.
    Childs, C.W., Downes, C.J., Platford, R.F.: Thermodynamics of aqueous sodium and potassium dihydrogen orthophosphate solutions at 25 °C. Aust. J. Chem. 26, 863–866 (1973)CrossRefGoogle Scholar
  13. 13.
    Kabiri-Badr, M., Zafarani-Moattar, M.T.: Volumetric and isopiestic studies of (H2O + K2HPO4 + KH2PO4) at 25 °C. J. Chem. Eng. Data 40, 412–414 (1995)CrossRefGoogle Scholar
  14. 14.
    Scharge, T., Muñoz, A.G., Moog, H.C.: Thermodynamic modelling of high salinity phosphate solutions. I. Binary systems. J. Chem. Thermodyn. 64, 249–256 (2013). (supplementary data) CrossRefGoogle Scholar
  15. 15.
    El Guendouzi, M., Benbiyi, A.: Thermodynamic properties of binary aqueous solutions of orthophosphate salts, sodium, potassium and ammonium at T = 298.15 K. Fluid Phase Equilib. 369, 68–85 (2014)CrossRefGoogle Scholar
  16. 16.
    Wood, R.H., Platford, R.F.: Free energies of aqueous mixtures of NaH2PO4 and NaClO4: evidence for the species \( ({\text{H}}_{2} {\text{PO}}_{4} )_{2}^{ - 2} \). J. Solution Chem. 4, 977–982 (1975)Google Scholar
  17. 17.
    Platford, R.F.: Thermodynamics of the system H2O–NaH2PO4–H3PO4. J. Chem. Eng. Data 21, 468–469 (1976)CrossRefGoogle Scholar
  18. 18.
    Filippov, V.K., Charykova, M.V., Trofimov, Yu.M.: Thermodynamic study of the system Na+,NH4 +|| SO4 2−–H2O and Na+, NH4 +|| H2PO4 –H2O at 25° (in Russian). Zh. Prikl. Khim. 60, 257–262 (1987); J. Appl. Chem. USSR (English translation) 60, 237–241 (1987)Google Scholar
  19. 19.
    Filippov, V.K., Charykova, M.V.: Phase equilibria in the system Na+||Cl, SO4 2−, H2PO4 –H2O at 25° (in Russian). Zh. Prikl. Khim. 64, 3–7 (1991); J. Appl. Chem. USSR (English translation) 64, 1–5 (1991)Google Scholar
  20. 20.
    Pavićević, V., Ninković, R., Todorović, M., Miladinović, J.: Osmotic and activity coefficients of {yNaH2PO4 + (1 – y)Na2SO4}(aq) at the temperature 298.15 K. Fluid Phase Equilibr. 164, 275–284 (1999)CrossRefGoogle Scholar
  21. 21.
    Childs, C.W., Downes, C.J., Platford, R.F.: Thermodynamics of multicomponent aqueous solutions: aqueous mixtures of two salts from among NaCl, KCl, NaH2PO4, and KH2PO4 at 25 °C. J. Solution Chem. 3, 139–147 (1974)CrossRefGoogle Scholar
  22. 22.
    Pitzer, K.S.: Ion-interaction approach: theory and data correlation. In: Pitzer, K.S. (ed.) Activity Coefficients in Electrolyte Solutions, 2nd edn. CRC Press, Boca Raton (1991). (Chap. 3) Google Scholar
  23. 23.
    Archer, D.G.: Thermodynamic properties of the NaCl + H2O system. II. Thermodynamic properties of NaCl(aq), NaCl·2H2O(cr), and phase equilibria. J. Phys. Chem. Ref. Data 21, 793–829 (1992)CrossRefGoogle Scholar
  24. 24.
    Clegg, S.L., Rard, J.A., Pitzer, K.S.: Thermodynamic properties of 0–6 mol kg−1 aqueous sulfuric acid from 273.15 to 328.15 K. J. Chem. Soc. Faraday Trans. 90, 1875–1894 (1994)CrossRefGoogle Scholar
  25. 25.
    Clegg, S.L., Pitzer, K.S., Brimblecombe, P.: Thermodynamics of multicomponent, miscible, ionic solutions. 2. Mixtures including unsymmetrical electrolytes. J. Phys. Chem. 96, 9470–9479 (1992); Corrections. 98, 1368 (1994)CrossRefGoogle Scholar
  26. 26.
    Treadwell, F.P.: Analytical Chemistry, Vol. II, Quantitative Analysis, 4th edn. (English translation of: Kurzes Lehrbuch der analytischen Chemie, Vol. II, Quantitative Analyse). Wiley, New York (1915)Google Scholar
  27. 27.
    Rard, J.A., Platford, R.F.: Experimental methods: isopiestic. In: Pitzer, K.S. (ed.) Activity Coefficients in Electrolyte Solutions, 2nd edn. CRC Press, Boca Raton (1991). Chap. 5 Google Scholar
  28. 28.
    Archer, D.G., Wang, P.: The dielectric constant of water and Debye–Hückel limiting law slopes. J. Phys. Chem. Ref. Data 19, 371–411 (1990)CrossRefGoogle Scholar
  29. 29.
    Scatchard, G.: Osmotic coefficients and activity coefficients in mixed electrolyte solutions. J. Am. Chem. Soc. 83, 2636–2642 (1961)CrossRefGoogle Scholar
  30. 30.
    Archer, D.G.: Thermodynamic properties of the KCl + H2O system. J. Phys. Chem. Ref. Data 28, 1–17 (1999)CrossRefGoogle Scholar
  31. 31.
    Makovička, J., Salomon, M.: Alkali metal othophosphates. In: Eysseltová, J., Dirske, T.D. (eds.) Solubility Data Series, vol. 31. Pergamon, Oxford (1988). https://srdata.nist.gov/solubility/IUPAC/SDS-31.aspx
  32. 32.
    Zhao, F., Lu, Y., Wang, K., Luo, G.: Solubility of KH2PO4 in KCl, H3PO4, and their mixture solutions. J. Chem. Eng. Data 59, 439–443 (2014)CrossRefGoogle Scholar
  33. 33.
    Zdanovskii, A.B.: Thermodynamics of mixed electrolyte solutions (in Russian). Tr. Solyanoi Lab. Akad. Nauk SSSR. No. 6 (1936)Google Scholar
  34. 34.
    Kirgintsev, A.N., Luk’yanov, A.V.: Isopiestic investigation of ternary solutions. VII. Ternary solutions lithium chloride–caesium chloride–water, potassium chloride–caesium chloride–water, rubidium chloride–caesium chloride–water, potassium chloride–calcium–water, and potassium chloride–magnesium chloride–water (English translation). Russ. J. Phys. Chem. 40, 686–688 (1966)Google Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • Tijana Ivanović
    • 1
  • Daniela Ž. Popović
    • 2
  • Jelena Miladinović
    • 2
  • Joseph A. Rard
    • 3
  • Zoran P. Miladinović
    • 4
  • Svetlana Belošević
    • 5
  • Katarina Trivunac
    • 2
  1. 1.Institute for Multidisciplinary ResearchUniversity of BelgradeBelgradeSerbia
  2. 2.Faculty of Technology and MetallurgyUniversity of BelgradeBelgradeSerbia
  3. 3.LivermoreUSA
  4. 4.Institute of General and Physical ChemistryBelgradeSerbia
  5. 5.Faculty of Technical SciencesUniversity of PrištinaKosovska MitrovicaSerbia

Personalised recommendations