Estimation of pH Values. (Living Tissues and Saps.)

  • J. Small
Part of the Modern Methods of Plant Analysis / Moderne Methoden der Pflanzenanalyse book series (PFLANZENANAL., volume 1)


The outlook of this section is peculiar, because there is already a vast literature dealing with theory, methods, and results; and the basis of theory and practical methods and results was officially admitted in 1950 to have been wrong. Therefore, all post-1950 work should be done with some idea of the new methods and the new limits placed upon the accuracy of the results. Practically all the pre-1950 pH values were calculated on E 0 = 0.2458 V for the saturated calomel electrode at 25° C. whereas the new standard value is E 0 = 0.2543 V, and this decrease of 1.5 mV in the reference value of E 0 means that 0.03 to 0.04 must be added to pre-1950 pH values in order to equate them with post-1950 pH values which are themselves subject to an accuracy-limit of at least ± 0.02. The common- sense limit in all ordinary estimations of pH values is an accuracy to the first decimal place with a range of ± 0.05 around the recorded first decimal. Greater accuracy can be obtained when pure unmixed chemical substances are used, but the estimation of pH values is not usually concerned with pure unmixed chemical substances, especially in plant analyses.


Pale Pink Indicator Method Indicator Solution Standard Buffer Solution Thymol Blue 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Bates, R. G.: Chem. Eev. 42, 1 (1948).Google Scholar
  2. Bates, R. G.: British Standards Institution (24/28 Victoria Street, Westminster, London S.W. 1.). pH Scale. British Standard. 1647 1950.Google Scholar
  3. Britton, H. T. S.: Hydrogen Ions. Vols. I and II. London 1942.Google Scholar
  4. Chambers, B., and T. Kerb: J. Cellular and Comp. Physiology 2, 105 (1932).CrossRefGoogle Scholar
  5. Clark, W. M.: The Determination of Hydrogen Ions. 3rd edition. London and Philadelphia 1928.Google Scholar
  6. Cooke, M. P.: Some aspects of stomatal physiology. Belfast: Thesis, Queen’s University 1952.Google Scholar
  7. Damboviceantj, A., and L. Rapkine: C. r. Soc. Biol. 93, 1346 (1925).Google Scholar
  8. Heilbrunn, L. V.: An Outline of General Physiology. 3rd Edit. Philadelphia & London 1952.Google Scholar
  9. Lngold, C. T, and J. SMALL: Protoplasma 3, 458 (1928).CrossRefGoogle Scholar
  10. Jenny, H. et al., Science 112, 164 (1950).PubMedCrossRefGoogle Scholar
  11. Martin, S. H.: Protoplasma 1, 497 (1927).CrossRefGoogle Scholar
  12. Michaelis, L.: Hydrogen Ion Concentration (trans. W. A. PERLZWEIG). Baltimore 1926.Google Scholar
  13. Mislowitzer, E.: Die Bestimmung der W.I.K, von Flüssigkeiten. Berlin 1928.Google Scholar
  14. National Bureau of Standards, U.S.A. (Department of Commerce, National Bureau of Standards, Washington, 25). Standardization of pH Measurements made with the Glass Electrode. Letter Circular LC 993, 1950Google Scholar
  15. Needham, J., and D.: Proc. Roy. Soc. (Lond.) 98B, 259 (1925)Google Scholar
  16. Proc. Roy. Soc. (Lond.) 99 B, 173 (1926)Google Scholar
  17. Bapkine, L., and R. Wurmser: C. r. Soc. Biol. 94, 989 (1926).Google Scholar
  18. Ricci, J. E.: Hydrogen Ion Concentration. Princeton 1952.Google Scholar
  19. RIETSEMA, J.: Meded. Bot. Lab. Utrecht 1950, No. 1.Google Scholar
  20. Scott-moncrieff, R.: J. Genet. 82, 117 (1936).CrossRefGoogle Scholar
  21. SMALL, J.: Protoplasma 1, 324 (1926)CrossRefGoogle Scholar
  22. Small, J.: Hydrogen-ion Concentration of Plant Cells and Tissues. Protoplasma Monographs No. 2. Berlin 1929Google Scholar
  23. Practical Botany. London: Churchill 1931. pH and Plants. London and New York 1946; Protoplasma 41, 273 (1952); Modern Aspects of pH. London 1954.Google Scholar
  24. Smith, E. P.: Protoplasma 18, 112 (1933).CrossRefGoogle Scholar
  25. Walling, C.: J. Amer. Chem. Soc. 72, 1164.Google Scholar

Copyright information

© Springer-Verlag OHG. Berlin Göttingen Heidelberg 1956

Authors and Affiliations

  • J. Small

There are no affiliations available

Personalised recommendations