Journal of Solution Chemistry

, Volume 6, Issue 12, pp 781–818 | Cite as

The hydration of anions in nonaqueous media

  • Edward M. Arnett
  • B. Chawla
  • N. J. Hornung


A very simple isopiestic method based on that of S. Christian is used for measuring the salting-in of water into nonpolar, low-volatility solvents by tetraalkylammonium salts. The quantity of excess water which is dissolved in such solvents is directly proportional to the salt concentration and is sharply dependent on the nature of the anion but is nearly insensitive to that of the R4N+ cation. The hydration ratioH, which we define as the moles of excess solubilized water per mole of R4N+ X, is directly relatable to the enthalpy of hydration of the anion X in several solvents and in the gas phase. The quantityH is also correlated with many free-energy terms including those for the Hofmeister lyotropic series, for the ability of the anions to salt nonelectrolytes out of water, for the free-energy terms for separation of these ions by reverse osmosis membranes, and for their nucleophilicities. A surprising (but not unprecedented) feature of the hydration ratio is that it, rather than its logarithm, behaves as a free-energy term. It is proposed that all these properties have in common the free energy of hydration of the anions, and this notion is supported by a close correspondence between the anionic hydration ratio and their hydrogen-bonding energies with proton donors in aprotic solvents. The results support scattered observations by other workers that isolated water molecules do not have an unusual inherent affinity for anions. Accordingly, large anionic hydration energies in bulk aqueous media reflect extensive cooperative interactions in the solvent. Implications for nucleophilic activity in phase transfer catalysis and enzyme activity are mentioned.

Key words

Isopiestic method salting-in of water tetraalkylammonium salts enthalpy of hydration free-energy terms Hofmeister lyotropic series nonelectrolytes reverse osmosis membranes nucleophilicites aprotic solvents 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    See Empedocles,Encyclopedia Britannica.Google Scholar
  2. 2.
    Water, A Comprehensive Treatise, F. Franks, ed. Vols. 1–5 (Plenum Press, New York, 1972–1975).Google Scholar
  3. 3.
    D. Eisenberg and W. Kauzmann,The Structure and Properties of Water (Oxford University Press, New York, 1969).Google Scholar
  4. 4.
    N. E. Ernest Dorsey,Properties of Ordinary Water-Substance, Am. Chem. Soc., Monograph Series No. 81 (Reinhold, New York, 1940).Google Scholar
  5. 5.
    J. L. Kavanau,Water and Solute-Water Interactions (Holden-Day, San Francisco, 1964).Google Scholar
  6. 6.
    C. Tanford,The Hydrophobic Effect (Wiley, New York, 1973).Google Scholar
  7. 7.
    R. L. Kay,The Physical Chemistry of Aqueous Solutions (Plenum, New York, 1973).Google Scholar
  8. 8.
    R. Lumry and S. Rajender,Biopolymers 9, 1125 (1970).Google Scholar
  9. 9.
    Water, A Comprehensive Treatise, F. Franks, ed., Vol. 2 (Plenum Press, New York, 1973), p. 371 and following.Google Scholar
  10. 10.
    S. C. Mohr, W. D. Wilk, and G. M. Barrow,J. Am. Chem. Soc. 87, 3048 (1965).Google Scholar
  11. 11.
    R. L. Benoit and S. Y. Lam,J. Am. Chem. Soc. 96, 7385 (1976).Google Scholar
  12. 12.
    R. L. Benoit and C. Buisson,Inorg. Chim. Acta 7, 256 (1973).Google Scholar
  13. 13.
    G. Choux and R. L. Benoit,J. Am. Chem. Soc. 91, 6221 (1969).Google Scholar
  14. 14.
    T. Kenjo and R. M. Diamond,J. Inorg. Nucl. Chem. 36, 183 (1974).Google Scholar
  15. 15.
    T. Kenjo and R. M. Diamond,J. Phys. Chem. 76, 2454 (1972).Google Scholar
  16. 16.
    T. Kenjo, S. Brown, E. Held, and R. M. Diamond,J. Phys. Chem. 76, 1775 (1972).Google Scholar
  17. 17.
    D. J. Turner, A. Beck, and R. M. Diamond,J. Phys. Chem. 72, 2831 (1968).Google Scholar
  18. 18.
    D. R. Cogley, J. N. Butler, and E. Grunwald,J, Phys. Chem. 75, 1477 (1971).Google Scholar
  19. 19.
    I. M. Kolthoff,Anal. Chem. 46, 1992 (1974).Google Scholar
  20. 20.
    I. M. Kolthoff and M. K. Chantooni, Jr.,J. Am. Chem. Soc. 91, 6907 (1969).Google Scholar
  21. 21.
    I. M. Kolthoff and M. K. Chantooni, Jr.,J. Am. Chem. Soc. 91, 25 (1969).Google Scholar
  22. 22.
    I. M. Kolthoff and M. K. Chantooni, Jr.,Anal. Chem. 39, 1080 (1967).Google Scholar
  23. 23.
    M. K. Chantooni, Jr., and I. M. Kolthoff,J. Am. Chem. Soc. 89, 1582 (1967).Google Scholar
  24. 24.
    I. M. Kolthoff and T. B. Reddy,Inorg. Chem. 1, 189 (1962).Google Scholar
  25. 25.
    I. D. Kuntz, Jr., and C. J. Cheng,J. Am. Chem. Soc. 97, 4852 (1975).Google Scholar
  26. 26.
    R. P. Taylor and I. D. Kuntz, Jr.,J. Phys. Chem. 74, 4573 (1970).Google Scholar
  27. 27.
    R. P. Taylor and I. D. Kuntz, Jr.,J. Am. Chem. Soc. 92, 4813 (1970).Google Scholar
  28. 28.
    R. P. Taylor and I. D. Kuntz, Jr.,J. Am. Chem. Soc. 94, 7963 (1972).Google Scholar
  29. 29.
    H. S. Frank,J. Chem. Phys. 13, 478, 493 (1945); H. S. Frank and M. W. Evans,J. Chem. Phys. 13, 507 (1945).Google Scholar
  30. 30.
    H. S. Frank and W. Y. Wen,Disc. Faraday Soc. 24, 133 (1957).Google Scholar
  31. 31.
    G. Nemethy and H. A. Scheraga,J. Chem. Phys. 36, 3382, 3401 (1962).Google Scholar
  32. 32.
    Water, A Comprehensive Treatise, F. Franks, ed., Vol. 3 (Plenum Press, New York, 1973), Chap. 1.Google Scholar
  33. 33.
    F. Franks and D. J. G. Ives,Q. Rev. Chem. Soc. 20, 1 (1966).Google Scholar
  34. 34.
    T. S. Sarma and J. C. Ahluwalia,Chem. Soc. Rev. 2, 203 (1973).Google Scholar
  35. 35.
    J. E. Gordon,The Organic Chemistry of Electrolyte Solutions (Wiley, New York, 1975).Google Scholar
  36. 36.
    A. P. Krueger and E. J. Reed,Science 193, 1209 (1976).Google Scholar
  37. 37.
    E. M. Arnett, N. Hornung, and R. Minasz,Colloques Internationaux du C.N.R.S. No. 246—L'Eau et les Systems Biologiques, Paris, 1975, p. 89.Google Scholar
  38. 38.
    S. D. Christian, H. E. Affsprung, J. R. Johnson, and J. D. Worley,J. Chem. Educ. 40, 419 (1963).Google Scholar
  39. 39.
    J. R. Johnson, P. J. Kilpatrick, S. D. Christian, and H. E. Affsprung,J. Phys. Chem. 72, 3223 (1968).Google Scholar
  40. 40.
    S. D. Christian, A. A. Taha, and B. W. Gash,Q. Rev. Chem. Soc. 24, 20 (1970).Google Scholar
  41. 41.
    J. Mitchell, Jr., and D. M. Smith,Aquametry (Interscience, New York, 1948).Google Scholar
  42. 42.
    J. Mitchell, Jr., inTreatise on Analytical Chemistry, I. M. Kolthoff, P. J. Elving, and E. B. Sandell, eds., Part II, Vol. 1 (Interscience, New York, 1962).Google Scholar
  43. 43.
    D. D. Perrin, W. L. E. Armarego, and D. R. Perrin,Purification of Laboratory Chemicals (Pergamon Press, London, 1966).Google Scholar
  44. 44.
    T. Tarui,J. Inorg. Nucl. Chem. 37, 1213 (1975).Google Scholar
  45. 45.
    D. J. Eatough, J. J. Christensen, and R. M. Izatt,Experiments in Thermometric Titrimetry and Titration (Brigham Young University Press, Provo, Utah, 1974).Google Scholar
  46. 46.
    B. G. Cox, G. R. Hedwig, A. J. Parker, and D. W. Watts,Aust. J. Chem. 27, 477 (1974).Google Scholar
  47. 47.
    E. M. Arnett, and D. R. McKelvey,J. Am. Chem. Soc. 88, 2598 (1966).Google Scholar
  48. 48.
    S. Goldman and W. C. Duer,Can. J. Chem. 52, 3919 (1974).Google Scholar
  49. 49.(a)
    Y. Yamamoto, T. Tarumoto, and E. Ewamoto,Anal. Chim. Acta 64, 1 (1973);Google Scholar
  50. 49.(b)
    Y. Yamamoto, T. Tarumoto, and T. Tarui,Bull. Chem. Soc. Jpn 46, 1466 (1973).Google Scholar
  51. 50.
    E. Charles Evers, Thesis, Brown University, May 1941.Google Scholar
  52. 51.
    G. J. Janz and R. P. T. Tompkins,Nonaqueous Electrolytes Handbook, Vol. 1, Sections III-F-3 and III-G-1a (Academic Press, New York, 1972).Google Scholar
  53. 52.
    L. P. Hammett,Physical Organic Chemistry, 2nd ed. (McGraw-Hill, New York, 1970), pp. 16–19; J. E. Leffler and E. Grunwald,Rates and Equilibria of Organic Reactions (Wiley, New York, 1963), pp. 33–38.Google Scholar
  54. 53.
    P. Kebarle, inIons and Ion Pairs in Organic Reactions, M. Szwarc, ed., Vol. 1, (Wiley-Interscience, New York, 1972).Google Scholar
  55. 54.
    P. Kebarle, inModern Aspects of Electrochemistry, B. E. Conway and J. O'M. Bockris, eds., Vol. 9 (Plenum Press, New York, 1974).Google Scholar
  56. 55.
    W. R. Davidson and P. Kebarle,J. Am. Chem. Soc. 98, 6133 (1976).Google Scholar
  57. 56.
    F. Hofmeister,Arch. Exp. Pathol. 24, 242 (1888);27, 395 (1890).Google Scholar
  58. 57.
    P. H. von Hippel,Colloques Internationaux du C.N.R.S. No. 246—L'Eau et les Systems Biologiques, Paris, 1975, p. 15.Google Scholar
  59. 58.
    P. H. von Hippel and T. Schleich,Acc. Chem. Res. 2, 257 (1969).Google Scholar
  60. 59.
    S. Loeb,Desalination by Reverse Osmosis, V. Merten, ed. (M.I.T. Press, Cambridge, Massachusetts, 1966), p. 86.Google Scholar
  61. 60.
    S. Sourirajan,Reverse Osmosis (Academic Press, New York, 1970), pp. 28–29.Google Scholar
  62. 61.
    T. Matsuura, L. Pageau, and S. Sourirajan,J. Appl. Polym. Sci. 19, 179 (1975).Google Scholar
  63. 62.
    J. M. Dickson, T. Matsuura, P. Blais, and S. Sourirajan,J. Appl. Polym. Sci. 19, 801 (1975).Google Scholar
  64. 63.
    P. H. von Hippel and A. Hamabata,J. Mechanochem. Cell Motil. 2, 127 (1973).Google Scholar
  65. 64.
    H. K. Lonsdale, inIndustrial Processing with Membranes, R. E. Lacey and S. Loeb, eds. (Wiley, New York, 1972), p. 155.Google Scholar
  66. 65.
    H. H. P. Fang and E. S. K. Chian,J. Appl. Polym. Sci. 19, 2889 (1975).Google Scholar
  67. 66.
    G. Eisenman,Proc. 23rd Int. Congr. Phys. Sci., Tokyo (Excerpta Med. Found., Amsterdam, 1965), pp. 489–506.Google Scholar
  68. 67.
    R. M. Diamond and E. M. Wright,Ann. Rev. Physiol. 31, 581 (1969).Google Scholar
  69. 68.
    F. A. Long and W. F. McDevit,Chem. Rev. 51, 119 (1952).Google Scholar
  70. 69.
    V. F. Sergeeva,Russ. Chem. Rev. 34, 309 (1965).Google Scholar
  71. 70.
    B. E. Conway, J. E. Desnoyers, and A. C. Smith,Philos. Trans. Roy. Soc. London, 389 (1964).Google Scholar
  72. 71.
    C. V. Krishnan and H. L. Friedman,J. Solution Chem. 3, 727 (1974).Google Scholar
  73. 72.
    J. E. Gordon,The Organic Chemistry of Electrolyte Solutions (Wiley-Interscience, New York, 1975), pp. 10–34.Google Scholar
  74. 73.
    D. R. Robinson and W. P. Jencks,J. Am. Chem. Soc. 87, 2470 (1965).Google Scholar
  75. 74.
    W. P. Jencks,Catalysis in Chemistry and Enzymology (McGraw-Hill, New York, 1969), Chap. 7.Google Scholar
  76. 75.
    E. D. Goddard, O. Kao, and H. C. Kung,J. Colloid Interface Sci. 27, 616 (1968), J. Ralston and T. W. Healy,J. Colloid Interface Sci. 42, 629 (1973).Google Scholar
  77. 76.
    J. E. Desnoyers and F. M. Ichhaporia,Can. J. Chem. 47, 4639 (1969).Google Scholar
  78. 77.
    R. L. Bergen, Jr., and F. A. Long,J. Phys. Chem. 60, 1131 (1956).Google Scholar
  79. 78.
    M. Alexandre and P. Lindenberg,Compt. Rend. 276, 721 (1948).Google Scholar
  80. 79.
    R. J. Lavese and W. J. Canady,J. Phys. Chem. 65, 1240 (1961).Google Scholar
  81. 80.
    W. Proudlock and D. Rosenthal,J. Phys. Chem. 73, 1695 (1969).Google Scholar
  82. 81.
    R. W. Taft, D. Gurka, L. Joris, P. von R. Schleyer, and J. W. Rakshys,J. Am. Chem. Soc. 91, 4801 (1969).Google Scholar
  83. 82.
    R. S. Drago,Struct Bonding (Berlin) 15, 73 (1973).Google Scholar
  84. 83.
    J. E. Gordon,J. Am. Chem. Soc. 94, 650 (1972); M. J. Tait and F. Franks,Nature 230, 91 (1971).Google Scholar
  85. 84.
    J. L. Beauchamp,Annu. Rev. Phys. Chem. 22, 527 (1971).Google Scholar
  86. 85.(a)
    J. F. Bunnett,Annu. Rev. Phys. Chem.,14, 271 (1963);Google Scholar
  87. 85.(b)
    F. L. Schadt, T. W. Bentley, and P. v. R. Schleyer,J. Am. Chem. Soc. 98, 7667 (1976).Google Scholar
  88. 86.
    R. C. Dougherty and D. Roberts,Org. Mass. Spectrom. 8, 81 (1974).Google Scholar
  89. 87.
    R. G. Pearson, H. Sobel, and J. Songstad,J. Am. Chem. Soc. 90, 3191 (1968).Google Scholar
  90. 88.
    R. J. Pearson,Advances in Linear Free Energy Relationship, N. B. Chapman and J. Shutter, ed. (Plenum Press, New York, 1972).Google Scholar
  91. 89.
    L. E. Strong and C. A. Kraus,J. Am. Chem. Soc. 72, 166 (1950).Google Scholar
  92. 90.
    A. C. Knipe,J. Chem. Educ. 53, 618 (1976).Google Scholar
  93. 91.
    C. M. Stark and R. M. Owens,J. Am. Chem. Soc. 95, 3616 (1973).Google Scholar
  94. 92.
    D. S. Kemp, D. D. Cox, and K. G. Paul,J. Am. Chem. Soc. 97, 7312 (1975).Google Scholar
  95. 93.
    G. N. Lewis and M. Randall,Thermodynamics, revised by K. S. Pitzer and L. Brewer, 2nd ed. (McGraw-Hill, New York, 1961), Chap. 34.Google Scholar
  96. 94.
    J. Leffler and E. Grunwald,Rates and Equilibria of Organic Reactions (Wiley, New York, 1963), pp. 28–29.Google Scholar
  97. 95.
    E. N. Lassettre,J. Am. Chem. Soc. 59, 1383 (1937).Google Scholar
  98. 96.
    C. R. Witschenke and C. A. Kraus,J. Am. Chem. Soc. 69, 2472 (1947).Google Scholar
  99. 97.
    A. Saek and R. M. Fuoss,J. Am. Chem. Soc. 76, 5905 (1954).Google Scholar
  100. 98.
    E. L. Strong and C. A. Kraus,J. Am. Chem. Soc. 72, 166 (1950).Google Scholar
  101. 99.
    E. Hirsch and R. M. Fuoss,J. Am. Chem. Soc. 82, 1018 (1960).Google Scholar
  102. 100.
    A. L. Powel and A. E. Martell,J. Am. Chem. Soc. 79, 2118 (1957).Google Scholar
  103. 101.
    R. M. Fuoss and E. Hirsch,J. Am. Chem. Soc. 82, 1013 (1960).Google Scholar
  104. 102.
    F. Accascina, E. L. Swarts, P. L. Mercier, and C. A. Kraus,Proc. Nat. Acad. Sci. U.S.A. 39, 917 (1953).Google Scholar
  105. 103.
    H. L. Curry and W. R. Gilkerson,J. Am. Chem. Soc. 79, 4021 (1957).Google Scholar
  106. 104.
    Y. H. Inami, H. K. Bodenseh, and J. B. Ramsay,J. Am. Chem. Soc. 83, 4745 (1961).Google Scholar
  107. 105.
    H. K. Bodenseh and J. B. Ramsay,J. Phys. Chem. 67, 143 (1963).Google Scholar
  108. 106.
    J. J. Zwolenik and R. M. Fuoss,J. Phys. Chem. 68, 903 (1964).Google Scholar

Copyright information

© Plenum Publishing Corporation 1977

Authors and Affiliations

  • Edward M. Arnett
    • 1
  • B. Chawla
    • 1
  • N. J. Hornung
    • 1
  1. 1.Department of ChemistryUniversity of PittsburghPittsburgh

Personalised recommendations