Journal of Solution Chemistry

, Volume 7, Issue 11, pp 845–858 | Cite as

Ionic association in acetonitrile and in formamide

  • P. C. Carman
Article

Abstract

In a recent derivation of relaxation effects in the Debye-Hückel-Onsager theory of electrolyte conductance, with a length parameter a, terms are included which have been omitted in earlier treatments (see Appendix). The new expression was applied earlier in a reanalysis of conductance data for aqueous solutions and is applied here to solutions in acetonitrile and in formamide, representing respectively dielectric constants considerably lower and higher than water. As in aqueous solutions, a minimum standard deviation is found over a wide range of (KA,a) pairs without much effect on A 0 , so that only approximate determinations ofKA are possible. On the whole, the most appropriate length parametera is the physical contact distance between counterions, not a fixed radius, independent of ionic size, such as the Bjerrum value, nor a much larger radiusR serving as a boudary between free and associated ions in the ionic atmosphere about a central ion. Relaxation effects calculated by the new analysis are smaller than those from previous expressions for equal values ofa, and this leads to considerably larger values ofKA than in the original papers. As a consequence, specific short-range ion-ion and ion-solvent forces in most solutions predominate over electrostatic attraction between counterions in their contribution toKA. A table of limiting equivalent conductance based on the A 0 values obtained is presented; this differs little from previous tables since A 0 values obtained by the new analysis are similar to those obtained originally.

Key words

Relaxation effects electrolyte conductance limiting conductance ionic association acetonitrile formamide 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    P. C. Carman,J. S. Afr. Chem. Inst. 28, 80 (1975).Google Scholar
  2. 2.
    P. C. Carman and D. P. Laurie,J. Solution Chem. 5, 457 (1976).Google Scholar
  3. 3.
    P. C. Carman,J. S. Afr. Chem. Inst. 28, 341 (1975).Google Scholar
  4. 4.
    P. C. Carman,J. Solution Chem. 6, 609 (1977).Google Scholar
  5. 5.
    E. M. Hanna, A. D. Pethybridge, and J. E. Prue,J. Phys. Chem. 75, 291 (1971).Google Scholar
  6. 6.
    W. C. Duer, R. A. Robinson, and R. G. Bates,J. Chem. Soc. Faraday Trans. 1 68, 716 (1972).Google Scholar
  7. 7.
    J-C. Justice,J. Chim. Phys. 65, 353 (1968).Google Scholar
  8. 8.
    A. D. Pethybridge and D. J. Spiers,J. Chem. Soc., Chem. Commun., 423 (1974).Google Scholar
  9. 9.
    R. M. Fuoss,J. Phys. Chem. 79, 525 (1975).Google Scholar
  10. 10.
    R. M. Fuoss,J. Phys. Chem. 80, 2091 (1976).Google Scholar
  11. 11.
    D. F. Evans, C. Zawoyski, and R. L. Kay,J. Phys. Chem. 69, 3878 (1965).Google Scholar
  12. 12.
    G. Jones and H. J. Fornewalt,J. Am. Chem. Soc. 57, 2041 (1935).Google Scholar
  13. 13.
    D. Feakins and K. G. Lawrence,J. Chem. Soc. A, 212 (1966).Google Scholar
  14. 14.
    D. Feakins, D. J. Fremantle and K. G. Lawrence,J. Chem. Soc. Faraday Trans. 1 70, 795 (1974).Google Scholar
  15. 15.
    J. Einfeldt and E. Gerdes,Z. Phys. Chem. (Leipzig) 246, 221 (1971).Google Scholar
  16. 16.
    F-T. Tuan and R. M. Fuoss,J. Phys. Chem. 67, 1343 (1963).Google Scholar
  17. 17.
    R. L. Kay, T. Vituccio, C. Zawoyski, and D. F. Evans,J. Phys. Chem. 70, 2336 (1966).Google Scholar
  18. 18.
    N-P Yao and D. W. Bennion,J. Electrochem. Soc. 118, 1097 (1971).Google Scholar
  19. 19.
    R. T. M. Bicknall, K. G. Lawrence, M. A. Shelley, D. Feakins, and L. Warblan,J. Chem. Soc. Faraday Trans. 1 72, 307 (1976).Google Scholar
  20. 20.
    W. Adolph and W. Seidel,Z. Phys. Chem. (Frankfurt) 93, 173 (1974).Google Scholar
  21. 21.
    R. Gopal and P. Singh,Indian J. Chem. 14A, 388 (1976).Google Scholar
  22. 22.
    J. M. Notley and M. Spiro,J. Chem. Soc. B, 352 (1966).Google Scholar
  23. 23.
    J. M. McDowell and C. A. Vincents,J. Chem. Soc. Faraday Trans. 1 70, 1862 (1974).Google Scholar
  24. 24.
    P. P. Rastogi,Bull. Chem. Soc. Jpn. 43, 2442 (1970).Google Scholar
  25. 25.
    G. Kortüm and C. Hebestreit,Z. Phys. Chem. (Frankfurt) 93, 235 (1974).Google Scholar
  26. 26.
    R. Gopal and P. P. Rastogi,Z. Phys. Chem. (Frankfurt) 69, 1 (1970).Google Scholar
  27. 27.
    L. M. Mukherjee and D. P. Boden,J. Phys. Chem. 73, 3965 (1969).Google Scholar
  28. 28.
    L. M. Mukherjee, D. P. Boden, and R. Lindauer,J. Phys. Chem. 74, 1942 (1970).Google Scholar
  29. 29.
    M. L. Jansen and H. L. Yeager,J. Phys. Chem. 77, 3089 (1973).Google Scholar
  30. 30.
    A. Sacco, G. Petrella, and M. Castagnio,J. Phys. Chem. 80, 749 (1976).Google Scholar
  31. 31.
    J-C. Justice and R. M. Fuoss,J. Phys. Chem. 67, 1707 (1963).Google Scholar
  32. 32.
    R. M. Fuoss,Pure Appl. Chem. 18, 125 (1968).Google Scholar
  33. 33.
    J. Thomas, and D. F. Evans,J. Phys. Chem. 74, 3813 (1970).Google Scholar
  34. 34.
    R. L. Kay, D. F. Evans, and G. P. Cunningham,J. Phys. Chem. 73, 3322 (1969).Google Scholar
  35. 35.
    F. Accascina, G. Pistola, and S. Schiavo,Ric. Sci. 36, 360 (1966).Google Scholar
  36. 36.
    R. L. Kay, B. J. Hales, and G. P. Cunningham,J. Phys. Chem. 71, 3925 (1967).Google Scholar
  37. 37.
    C. H. Springer, J. F. Coetzee, and R. L. Kay,J. Phys. Chem. 73, 471 (1969).Google Scholar
  38. 38.
    J. F. Coetzee and G. P. Cunningham,J. Am. Chem. Soc. 87, 2529 (1965).Google Scholar
  39. 39.
    D. S. Berns and R. M. Fuoss,J. Am. Chem. Soc. 82, 5585 (1960).Google Scholar
  40. 40.
    H. L. Yeager and B. Kratochvil,J. Phys. Chem. 74, 963 (1970).Google Scholar
  41. 41.
    R. A. Robinson and R. H. Stokes,Electrolyte Solutions (Butterworths Scientific Publications, London, 1959), p. 125.Google Scholar
  42. 42.
    W. L. Masterton, D. Bolocofsky, and T. P. Lee,J. Phys. Chem. 75, 2809 (1971).Google Scholar
  43. 43.
    C. Treiner and J-C. Justice,J. Chim. Phys. 65, 1516 (1968).Google Scholar
  44. 44.
    R. L. Kay,J. Am. Chem. Soc. 82, 2099 (1960).Google Scholar
  45. 45.
    R. M. Fuoss,J. Am. Chem. Soc. 80, 5059 (1958).Google Scholar
  46. 46.
    A. D'Aprano and I. D. Donato,J. Chem. Soc. Faraday Trans. 1 69, 1685 (1973).Google Scholar
  47. 47.
    F. Conti and G. Pistoia,J. Phys. Chem. 72, 2245 (1968).Google Scholar
  48. 48.
    A. D'Aprano,J. Solution Chem. 3, 363 (1974).Google Scholar
  49. 49.
    M. Goffredi and R. Triolo,J. Chem. Soc. Faraday Trans. 1 68, 2324 (1972).Google Scholar
  50. 50.
    A. D'Aprano, M. Goffredi, and R. Triolo,J. Chem. Soc. Faraday Trans. 1 71, 1188 (1975).Google Scholar
  51. 51.
    R. M. Fuoss,J. Solution Chem. 6, 335 (1977).Google Scholar
  52. 52.
    R. M. Fuoss, L. Onsager, and J. F. Skinner,J. Phys. Chem. 69, 2581 (1965).Google Scholar
  53. 53.
    P. C. Carman,J. S. Afr. Chem. Inst. 28, 264 (1975).Google Scholar

Copyright information

© Plenum Publishing Corporation 1978

Authors and Affiliations

  • P. C. Carman
    • 1
  1. 1.National Chemical Research LaboratoryCouncil for Scientific and Industrial ResearchPretoriaRepublic of South Africa

Personalised recommendations