Berzelius, Liebig, and Wöhler: An interesting "chemical triad" - Journal

Nov 1, 1976 - Berzelius, Liebig, and Wöhler: An interesting "chemical triad". Roger Rea. J. Chem. Educ. , 1976, 53 (11), p 715. DOI: 10.1021/ed053p715...
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and electrons incorporated into the nucleus itself. A sufficient number of protons were assigned to the nucleus t o give the required Atomic Mass, electrons equal in number to the Atomic Number were olaced around the nucleus, and then additional electrons were placed inside the nucleus to neutralize the "extra protons (2.3). (See accompanying diagram, taken from Ref. (Q))

Diagram of the Isotopes of Chlorine Atoms as depicted in textbooks of that era are somewhat startling to those of us accustomed to modern representations, but if nuclear reactions such as l3 decay and K-electron capture are considered, perhaps the older models are not so outlandish after all. Llterature Clted (11 Paulina. L.."GeneralChunistrv."3dad., W . H.FreemanandCo..San h e i a m , 1970, p. 88 121 Simon, W.,Base,D..andKranfl.Jr..J.C.,"AManualofCh~mistry."LeaandFchigar, Philadelphia, 1927. p. 119. (31 Naylo,, N. M., and Le Vesc0nte.A.. "lnVoductoryChemisf'~,"TheCent"ryCo,Near York,

1933.p.180.

Berzelius, Liebig, and Wohler: ~n Interesting "Chemical Triad" Roger R e a ~o;thwest High School Omaha, Ne. 68134 Jons Jakob Berzelius (1779-1848) and Justus Liebig (1803-1873) were two of the best known chemists of the early 1800's. Their relationship alternated between warm admiration and harsh, professional criticism; i t was their mutual friend, Friedrich Wohler, who served as the buffer between the volatile Liebig and the aging, opinionated Berzelius. Berzelius was the editor of Jahresbricht; Liebig edited the Annalen der Pharmacie. Neither man could avoid controversy; both men attacked the work of their fellow chemists by inserting critical and caustic footnotes in publications appearing in their journals. However, Liebig himself rarely responded favorably to criticism. Perhaps the best known of his controversies surrounded the publication of his "Animal Chemistry" ( I ) . Both Berzelius and Wohler were involved in the matter. Liebig's treatise on agricultural chemistry had been published in 1840 (2). The book contained many references to nutritional processes in animals, suggesting, for example, that fat can be accumulated in animals either by increasing the amount of food eaten or decreasing respiration so that less is oxidized. Liebig believed that the heat produced in an animal body was due to oxidations occurring within the animal. He

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nublished some of his views on this theorv of chemical heat prior to the release of "Animal ~hemistry.';~eneliusfelt that anv theorv of chemical heat was not sufficientlv well establisked to 6e used as an axiom, and had writteniiebig of his opinion, saying (3) ~

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You will easily see, my dear Liebig, that you are here standing on hollow ground, and that whatever you build must, in spite of your talent, sooner or later fall to pieces. Liebig was especially anxious to please Berzelius with the publication of "Animal Chemistry" in 1842, since he regarded ' Berzelius as the only real authority on physiological chemistry. Berzelius accepted Liehig's offer that the book be dedicated to him, hut declined any praiseful tribute on the grounds that it would appear to he an attempt to prevent his public criticism of thkbook. In 1843 Berzelius wrote (4) a mildly critical review of "Animal Chemistry," saying For animal chemistry the time has come. . . in which chemists. . . sketch for us in rapid strokes the chemical phenomena which occur in vital processes. This facile kind of physiological chemistry is created at the writing table, and is the more dangerous.. .because the majority of the readers will not be in aposition to distinguishwhat is right from the mere possibilities and probabilities, and will be misled into taking probabilities far truths.. . .

Liehig took Berzelius'attitude as a sign of personal hostility. Since he learned of Berzelius' opiniuns from Wohler, who translated Berzelius'articles into German for Liebie to read. L~ebigfclt that M'ohler, too, was deserting him over the incie ~lashine out at all the dent. Wohler wrote ( 5 ) ."He ( L i e b ~ is world, he is being attacked from afsides, whGh quite naturallv could have been ~redicted." when Berzelius failed to retract his criticism or modify his position, Liebig wrote in his Annnlen that Berzelius could not recognize that animal chemistry had advanced beyond the staae before, and continued (6); . - of his own work thirty. years ". . . so comes a man, my friend, the highest authority in science, and dares to stamp the theoretical expression of all this work as a play of fantasy." Berzelius replied that it was unfortunate that his work and opinions were of little value in Liebig's view, but that counter-criticisms in no way helped answer the questions he raised about "Animal Chemistry" (7). Berzelius could not understand Liebig's reaction to his review of "Animal Chemistry." He felt that his public criticism was actuallv ouite mild. He had written Wohler in private (8)."Mv God, s;& drivel!" Attemots were made to reconcile the differences between Liebig ar;d Berzelius when Berzelius visited Germany in 1845. While both men seemed receotive to a meetina, neither would ~. go more than half way to insire their r e n e ~ e i f r i e n d s h iNo meetine occurred. and Berzelius and Liebia- remained enemies until ~ k z e l i u sdeath ' in 1848. Literature Clted (1) Licbig, Juatus, "Animal Chemia~y," (Editor Gregory, William1 Taylor and Waitan. Landon, 1842. (2) Liebig,Justus, '"OrganieChemiatry in it.ApplicationatoAgrieulture mdPhy8iolon." (Editor: Playfair. Lyan) Taylor and Walton. London. 1840. (3) Shenstone,W. A.,"J"at"avonLiebig,HiaLifeand Work," Mamillisnand Co..Lond"n.

Volume 53, Number 11, November 1976 / 715