Abstract
Buffer solutions composed of 2-aminopyridinium chloride and 2-aminopyridine in synthetic seawater are useful as a supplement to buffers of ‘Tris’ (pH 8.2) and ‘Bis’ (pH 8.8) in standardizing measurements of hydrogen ion concentration (pm H or pH(SWS)) in oceanography. The dissociation constant of 2-amino-pyridinium ion over the range of salinities (S) from 30 to 40 has now been determined from the emf of cells without liquid junction at eight temperatures (T) from 278.15 to 313.15 K. The results fit the equation pK=2498.31/T−15.3274+2.4050 lnT+S(0.012928−2.9417×10−5T) with a standard deviation of 0.0023. Thermodynamic constants for the dissociation process and standard reference values of pm H and pH(SWS) were derived from the data. The pm H of the buffer consisting of 2-aminopyridinium chloride and 2-aminopyridine (each 0.04 molal) in synthetic seawater of salinity 35 varies from 7.356 at 278.15 K to 6.601 at 313.15 K.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
K. H. Khoo, C. H. Culberson, and R. G. Bates,J. Solution Chem. 6, 281 (1977).
R. W. Ramette, C. H. Culberson, and R. G. Bates,Anal. Chem. 49, 867 (1977).
R. G. Bates and J. G. Calais,J. Solution Chem. 10, 269 (1981).
J. B. Czerminski, A. G. Dickson, and R. G. Bates,J. Solution Chem. 11, 79 (1982).
W. H. Smith, Jr., and D. W. Hood,Recent Advances in the Fields of Hydrosphere, Atmosphere, and Nuclear Geochemistry (Maruzen, Tokyo, 1964), p. 185.
I. Hansson,Deep-Sea Res. 20, 479 (1973).
T. Almgren, D. Dyrssen, and M. Strandberg,Deep-Sea Res. 22, 635 (1975).
R. G. Bates and H. B. Hetzer,J. Res. Natl. Bur. Stand. A64, 427 (1960).
M. Yoshio and R. G. Bates,J. Chem. Eng. Data 26, 246 (1981).
D. Dyrssen and L. G. Sillén,Tellus 19, 113 (1967).
R. G. Bates and J. B. Macaskill, ‘Analytical Methods in Oceanography’, inAdvances in Chemistry Ser. 147, T. R. P. Gibb, Jr., ed., (American Chemical Society, Washington, 1975), p. 110.
R. G. Bates, ‘The Nature of Seawater’, inPhys. Chem. Sci. Res. Rpt. 1, E. D. Goldberg, ed., (Dahlem Konferenzen, Berlin, 1975), p. 313.
K. H. Khoo, R. W. Ramette, C. H. Culberson, and R. G. Bates,Anal. Chem. 49, 29 (1977).
R. G. Bates and J. B. Macaskill,Pure Appl. Chem. 50, 1701 (1978).
R. G. Bates, E. A. Guggenheim, H. S. Harned, D. J. G. Ives, G. J. Janz, C. B. Monk, J. E. Prue, R. A. Robinson, R. H. Stokes, and W. F. K. Wynne-Jones,J. Chem. Phys. 25, 361 (1956);26, 222 (1957).
A. G. Dickson and J. P. Riley,Mar. Chem. 7, 89 (1979).
R. G. Bates,Determination of pH, Theory and Practice, 2nd edn. (Wiley, New York, 1973), Chap. 10.
L. A. Bromley, D. Singh, P. Ray, S. Sridhar, and S. M. Read,AIChE J. 20, 326 (1974).
D. J. G. Ives and P. G. N. Moseley,J. Chem. Soc., Faraday Trans. I 72, 1132 (1976).
A. G. Dickson,Geochim. Cosmochim. Acta 48, 2299 (1984).
I. Hansson,Deep-Sea Res. 20, 461 (1973).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Bates, R.G., Erickson, W.P. Thermodynamics of the dissociation of 2-aminopyridinium ion in synthetic seawater and a standard for pH in marine systems. J Solution Chem 15, 891–901 (1986). https://doi.org/10.1007/BF00646030
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00646030