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Lajos Winkler

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Lajos Winkler (18631939) was a Hungarian analytical chemist. He is best known today for his discovery of the Winkler method for the measurement of oxygen dissolved in water.

Dissolved oxygen

Natural water contains molecular oxygen (O2), necessary for life in ponds, rivers, and so on. A common nineteenth-century for determining dissolved oxygen, as described by Alfred Wanklyn, involved boiling the water sample and collecting, over mercury, the gases released, for subsequent analysis.[1]

In 1888, while still a doctoral student, Lajos Winkler discovered a much safer, and more precise, method of dissolved-oxygen analysis, which is still widely used today.[2] The Winkler method uses the dissolved oxygen to convert manganese(II) hydroxide into manganese(III) hydroxide, and then analyzing for the latter by titration. The relevant chemical reactions are in print.[3]

See also

Further reading

  • McCormick, Patrick G. (1972). "The Determination of Dissolved Oxygen by the Winkler Method. A Student Laboratory Experiment". The Journal of Chemical Education. 49: 839–841.

References

  1. ^ Wanklyn, J. Alfred (1907). Water-Analysis, A Practical Treatise on the Examination of Potable Water (11 ed.). Kegan Paul, Trench, Trübner, and Co. Ltd. pp. 131–134. Retrieved 2008-02-09.
  2. ^ Winkler, L. W. (1888). "Die Bestimmung des in Wasser Gelösten Sauerstoffen". Berichte der Deutschen Chemischen Gesellschaft. 21: 2843–2855.
  3. ^ Crosson, Mary; Gibb, Reen (1992), "Dissolved Oxygen and Chloride Determination in Water", The Journal of Chemical Education, 69: 830–832
- See also the complete on-line copy here.
- Uses a modified Winkler method and shows a Winkler bottle