Johann Wolfgang Döbereiner
Encyclopedia
Johann Wolfgang Döbereiner (December 13, 1780 – March 24, 1849) was a German
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 chemist
Chemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....

 who is best known for work that foreshadowed the periodic law for the chemical element
Chemical element
A chemical element is a pure chemical substance consisting of one type of atom distinguished by its atomic number, which is the number of protons in its nucleus. Familiar examples of elements include carbon, oxygen, aluminum, iron, copper, gold, mercury, and lead.As of November 2011, 118 elements...

s.

Life and work

As a coachman's son, Döbereiner had little opportunity for formal schooling, and so he was apprenticed to an apothecary, reading widely, and attending science lectures. He eventually became a professor at the University of Jena
Jena
Jena is a university city in central Germany on the river Saale. It has a population of approx. 103,000 and is the second largest city in the federal state of Thuringia, after Erfurt.-History:Jena was first mentioned in an 1182 document...

 in 1810. In work beginning in 1829, Döbereiner discovered trends in certain properties of selected groups of elements. For example, the average atomic mass of lithium and potassium was close to the atomic mass of sodium. A similar pattern was found with calcium, strontium, and barium, with sulphur, selenium, and tellurium, and also with chlorine, bromine, and iodine. Moreover, the densities for some of these triads followed a similar pattern. These sets of elements became known as "Dobereiner's Triads
Dobereiner's Triads
Before the creation of the periodic table by Mendeleev, there were several laws for the classification of the elements. One of such laws was, Dobereiner's Law of Triads...

".

Döbereiner also is known for his discovery of furfural
Furfural
Furfural is an organic compound derived from a variety of agricultural byproducts, including corncobs, oat, wheat bran, and sawdust. The name furfural comes from the Latin word , meaning bran, referring to its usual source....

, for his work on the use of platinum
Platinum
Platinum is a chemical element with the chemical symbol Pt and an atomic number of 78. Its name is derived from the Spanish term platina del Pinto, which is literally translated into "little silver of the Pinto River." It is a dense, malleable, ductile, precious, gray-white transition metal...

 as a catalyst, and for a lighter, known as Döbereiner's lamp
Döbereiner's lamp
Döbereiner's lamp is a lighter invented in 1823 by the German chemist Johann Wolfgang Döbereiner, the lighter is based on the Fürstenberger lighter and was in production until ca. 1880. In the jar, zinc metal reacts with sulfuric acid to produce hydrogen gas. When a valve is opened, a jet of...

.

The German writer Goethe was a friend of Döbereiner, attended his lectures weekly, and used his theories of chemical affinities as a basis for his famous 1809 novella Elective Affinities
Elective Affinities
Elective Affinities , also translated under the title Kindred by Choice, is the third novel by Johann Wolfgang von Goethe, published in 1809. The title is taken from a scientific term once used to describe the tendency of chemical species to combine with certain substances or species in preference...

.
World of Scientific Discovery on Johann Wolfgang Döbereiner
The earliest years of Döbereiner's life did not suggest a brilliant future. He was born in Hof, Bavaria, on December 13, 1780, of poor parents. His father was a coachman who could provide Johann with only the most basic education. Although Döbereiner did attend a few lectures in chemistry, botany, mineralogy, philosophy, and languages, he was largely self-taught. Yet, he developed unusual skill in chemical research and caught the eye of Duke Carl August
Carl August, Grand Duke of Saxe-Weimar-Eisenach
Karl August, Grand Duke of Saxe-Weimar-Eisenach was a duke of Saxe-Weimar and of Saxe-Eisenach from 1758, duke of Saxe-Weimar-Eisenach from its creation in 1809, and grand duke from 1815 until his death...

 in 1810. Duke Carl appointed Döbereiner to the position of professor extraordinary in chemistry at Jena, a position he held throughout the rest of his academic life.
Döbereiner was a man of far-ranging interests and accomplishments. He conducted research on the manufacture of vinegar, the abundance of elements in the Earth's crust, the use of mineral waters for medical purposes, and many other topics in general, pharmaceutical, and analytical chemistry. In 1831 he discovered the chemical compound furfural, obtained from corn cobs, oat and rice hulls, and other cellulose-containing materials. He was one of the first chemists to offer laboratory instruction in chemistry.
In the early 1820s, Döbereiner studied the role of platinum metal as a catalyst. Somewhat earlier, Sir Humphry Davy had observed that heated platinum wire greatly increased the rate at which organic compounds oxidize. Döbereiner's contribution was to show that finely divided platinum ("platinum sponge") was even more effective than was solid platinum metal. He even invented a lighter that would generate a flame when gaseous hydrogen came into contact with a spongy platinum catalyst.
Most students recognize Döbereiner's name, however, for his contribution to the development of the periodic law. One consequence of Jöns Berzelius ' work on atomic weights was the realization by chemists that the properties of elements might be related to these atomic weights. Around 1817, Döbereiner noticed a pattern among three elements with similar chemical properties, chlorine, bromine, and iodine. Specifically, he noted that the atomic weight of bromine (80.970) was the arithmetic mean of the atomic weights of chlorine (35.470) and iodine (126.470). The currently accepted atomic weight for bromine was 80.470. Furthermore, the properties of the three elements varied in an orderly manner, from chlorine to bromine to iodine. Döbereiner spoke of this group of elements as a triad. He found two other triads among the known elements. One triad consisted of calcium, strontium, and barium; the other of sulfur, selenium, and tellurium.
Other chemists attempted to find other triads among the elements, but, overall, Döbereiner's discovery seemed to be a dead end. Thus, chemists largely ignored the Law of Triads. Not until Dmitri Mendeleev's discovery of the periodic law four decades later did the significance of Döbereiner's discovery finally become apparent.
Döbereiner died at Jena on March 24, 1849, twenty years before Mendeleev published his periodic law.

Further reading

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