Julius Tafel

Julius Tafel ( born June 2, 1862 in Choindez (municipality Courrendlin, then the Canton of Berne, Switzerland ), † September 2, 1918 in Munich) was a German chemist. He was the fourth child of Julius Tafel and his wife Berta, born Kinzelbach.

Career

• PhD in 1884 under the direction of Hermann Emil Fischer,
• 1888 Associate Professor in Würzburg,
• 1898 Adjunct Professor ( Professor A.O. )
• 1902 Professor of Inorganic and Analytical Chemistry University of Würzburg,
• 1903 Full Professor and Head of the Chemical Institute of the University of Würzburg.

When Emil Fischer worked on the synthesis of carbohydrates, Blackboard was his most important assistant - this work (1887 - 1889). Panel led from the experiments, as a fisherman for the first time in 1890 before the Chemical Society in Berlin reported on this work. As a fisherman went to Berlin, was Hantzsch successor in Würzburg; as Hantzsch in 1903 moved to Leipzig, plaque was his successor in Würzburg. In 1910 he had to retire due to his ill health from work. Out of desperation about his terminal illness, he retired in 1918 in Munich committed suicide.

Discoveries

The following terms in organic chemistry owes its name Julius Tafel:

• Panel rearrangement in organic chemistry: from Julius Tafel in 1907 discovered skeletal rearrangement in the electrolytic reduction of substituted acetoacetic esters in alcoholic sulfuric acid at a lead cathode.
• Panel law or relationship: Electrochemistry: at a sufficiently high overvoltage of the logarithm of the current is a linear function of the overvoltage (instead of overvoltage can also be tension between the working and reference electrode say) ( panel law or relation or relationship ).
• Board Gradient: Electrochemistry: the slope of the plot according to (2 ) ( table slope); the application is called in english panel line
• Table mechanism: Electrochemistry: in the electrolytic hydrogen evolution of the mechanism in which first under charge transfer adsorbed hydrogen atoms: are formed (MH M = metal atom of the electrode surface, H = hydrogen atom), which is then catalytically recombine: 2 MH -> 2 M H2 ( H2 = a hydrogen molecule). ( Panel mechanism. )
• Electrocatalysis: table found in particular, that of platinum, the overvoltage for hydrogen evolution (including recombination, see Figure 4) is low, so that only occurs hydrogen deposition on a platinum electrode in an aqueous solution, but no reduction of organic substances; However, to lead the overpotential for the hydrogen evolution is very high, so that, before the hydrogen evolution takes place, organics can be reduced; He gained this knowledge when he found that strychnine can be reduced to lead electrodes, which he used to its structural elucidation. Immediately thereafter he explored this whole matter, and thus became the founder of a branch of knowledge of electrochemistry, namely electrocatalysis. ( The catalysis on metal surfaces was known, but the specific circumstances of electrodes = metal surfaces in solutions to which a voltage is applied, lead to entirely new possibilities. ) During his lifetime, these findings have been widely ignored. He was ahead of the times and always found opportunity to criticize textbooks that they set no modern aspects of the reaction rate ( the "theory of reaction rates", for which he had with the panel equation laid the first foundation was only much later systematically developed ).

Predecessor to the chem. Institutions in Würzburg

• Adolph Strecker (1869-1871 †; Chem Institute in Maxstr 4. )
• John Wislicenus (1872-1885; Chem Institute in Maxstr 4. )
• Emil Fischer (1885-1892; Chem Institute in Maxstr 4. )
• Arthur Hantzsch (1893-1903; Chem. Institute in Maxstr 4, 1896 at the new Chem Inst Pleicher ring 11 )