Baron JÃÆ'¶ns Jacob Berzelius ( Swedish: Ã, [joens? J ?: K? B bö Se, li? S] ; August 20, 1779 - August 7, 1848), named by himself and contemporary society as Jacob Berzelius , was a Swedish chemist. Berzelius is considered, along with Robert Boyle, John Dalton, and Antoine Lavoisier, to become one of the founders of modern chemistry.
Berzelius began his career as a physician but his research in physical chemistry had a lasting meaning in the development of the subject. He is especially famous for his determination against atomic weights; his experiments led to a more complete description of the stoichiometric principles, or the combined field of chemical proportions. In 1803 Berzelius demonstrated the power of electrochemical cells to break down chemicals into electrically opposite constituent pairs.
Berzelius's work with atomic weights and his theory of electrochemical dualism leads to the development of a modern system of chemical formula notations that can describe any composition of a compound qualitatively (by demonstrating electrochemically opposed materials) and quantitatively (by showing the proportions the material is united). The system abbreviates the Latin names of elements with one or two letters and applied superscripts to determine the number of atoms of each element present in both acid and base materials.
Berzelius himself discovered and isolated several new elements, including cerium (1803) and thorium (1828). Berzelius's interest in mineralogy also fosters his analysis and preparation of these new compounds and other elements. The berzelianite mineral was discovered in 1850 and is named after its name. He is a rigorous empiricist and insists that every new theory is consistent with the amount of chemical knowledge. He developed classical analytical techniques, and investigated isomerism and catalysis, a phenomenon that owes their name to him. He became a member of the Royal Swedish Academy of Sciences in 1808 and served from 1818 as his main functionary, a perpetual secretary. He is known in Sweden as "Father of Chemistry of Sweden". Berzelius Day is celebrated on August 20 in his honor.
Video Jöns Jacob Berzelius
Biography
Berzelius was born in the VÃÆ'¤versunda parish in ÃÆ' â € "stergÃÆ'¶tland in Sweden. His father was a school teacher in the town near LinkÃÆ'¶ping and his mother a housewife. Berzelius lost both parents at an early age; his father died in 1779, and his mother in 1787. Relatives in LinkÃÆ'¶ping took care of him, and there he attended the school now known as Katedralskolan. He then enrolled at the University of Uppsala, where he studied the medical profession from 1796 to 1801; Anders Gustaf Ekeberg, the inventor of tantalum, taught him chemistry. He works as an apprentice at a pharmacy and with a doctor at the Medevi mineral springs. During this time, he analyzed the springs. For his medical studies, he examined the effect of galvanic currents on several diseases and graduated as M.D. in 1802. He worked as a doctor near Stockholm until the mine owner Wilhelm Hisinger discovered his analytical abilities and gave him a laboratory. Between 1808 and 1836, Berzelius collaborated with Anna SundstrÃÆ'¶m, who acted as his assistant.
In 1807, Berzelius was appointed professor of chemistry and pharmacy at the Karolinska Institute.
In 1808, he was elected to the Royal Swedish Academy of Sciences. By this time, the Academy has been stagnant for several years, since the era of romance in Sweden has led to a lack of interest in science. In 1818, Berzelius was elected secretary of the Academy and held the post until 1848. During the time of Berzelius, he was credited with reviving the Academy and bringing him into a second golden era (the first of which was the astronomer Pehr Wilhelm Wargentin as secretary from 1749 to 1783). He was elected a Foreign Honorary Member of the American Academy of Art and Science in 1822. In 1827, he became a correspondent of the Royal Netherlands Institute, and in 1830 an associate member. In 1837, he was elected a member of the Swedish Academy, in seat number 5.
Maps Jöns Jacob Berzelius
Achievements
Legal of definite proportion
Shortly after arriving in Stockholm, he wrote a chemistry textbook for medical students, from which a long and fruitful career in chemistry began. In 1813, he published an essay on the proportion of elements in the compound. This essay begins with a general description, introduces its new symbolism, examines all known elements, including certain weights tables, and completes with the selection of compounds written in its new formalization. In 1818, he compiled a table of relative atomic weights, in which oxygen was set to 100, and which included all elements known at the time. This work provides evidence that supports the atomic theory put forward by John Dalton: that inorganic chemistry is composed of atoms combined in total. In discovering that the weight of atoms is not an integral multiple of the weight of hydrogen, Berzelius also refutes the Prout hypothesis that the elements are built from hydrogen atoms. Berzelius atomic weight table was first published in its German translation of Textbook of Chemistry in 1826.
Chemical notation
To help his experiments, he developed a chemical notation system in which elements are labeled in simple writing - such as O for oxygen, or Fe for iron - with the proportion noted by numbers. This is the same system used today, the only difference being that instead of the current subscript number (eg, H 2 O), Berzelius uses superscript (H 2 O).
Discovery element
Berzelius is credited with identifying the chemical elements of silicon, selenium, thorium, and cerium. Students working in Berzelius's laboratory also discovered lithium and vanadium. Berzelius finds silicon by repeating experiments conducted by Gay-Lussac and ThÃÆ' Â © nard. In the experiment, Berzelius reacts to silicon tetrafluoride with a potassium metal and then purified its product by washing it up into a cocoa powder. Berzelius recognizes this brown powder as a new element of silicon, which he calls silicium, a name proposed earlier by Davy.
New chemical terms
Berzelius is credited with deriving the chemical terms "catalysis," "polymers," "isomers," and "allotropes," although the original definition differs dramatically from modern usage. For example, he coined the term "polymer" in 1833 to describe an organic compound having the same empirical formula but differing in the overall molecular weight, the larger the compound described as the smallest "polymer." At this time the concept of chemical structure has not been developed so that it only considers the number of atoms of each element, and is seen as an example of glucose (C 6 H 12 O 6 ) as formaldehyde polymers (CH 2 O) contradict modern usage. Berzelius also developed an electrochemical dualism.
Biology
Berzelius was the first to make a distinction between organic compounds (which contain carbon), and inorganic compounds. In particular, he advises Gerardus Johannes Mulder in analyzing the elements of organic compounds such as coffee, tea, and various proteins. The term protein itself was created by Berzelius, after Mulder observed that all proteins seem to have the same empirical formula and come to the erroneous conclusion that they may consist of one very large type of molecule. Berzelius proposes the name because it appears to be the primitive substance of animal nutrition that plants prepare for herbivores.
Vitalism
Berzelius declared in 1810 that living things work with a mysterious "vital force", a hypothesis called vitalism. Related to this, he proposes that compounds can be distinguished by whether they require any organism in their manufacture (organic compounds) or whether they are not (inorganic compounds). However, in 1828, Friedrich WÃÆ'¶hler accidentally obtained urea, an organic compound, by heating the ammonium cyanate. Contrary to widespread myth, that is not the end of this vitalist hypothesis, let alone vitalism in general. But in 1845 Adolph Wilhelm Hermann Kolbe prepared acetic acid from an inorganic precursor, and by the 1850s, Marcellin Berthelot synthesized many organic compounds from inorganic precursors, providing abundant evidence. The Fischer-Tropsch process for making hydrocarbons, the Miller-Urey experiment and other prebiotic-chemical experiments, and the biosynthetic pathway provides more evidence.
Relationships with other scientists
Berzelius is a prolific correspondent with prominent scientists such as Gerardus Johannes Mulder, Claude Louis Berthollet, Humphry Davy, Friedrich Wörler and Eilhard Mitscherlich.
After a long denial that chlorine is an element (as proposed by Humphry Davy in 1810), the dispute concludes with the discovery of iodine in 1812.
Family
In 1818 Berzelius was glorified by King Carl XIV Johan; in 1835, at the age of 56, he married Elisabeth Poppius, daughter of minister of Sweden minister 24 years old, and in the same year was appointed friherre.
Berzeliusskolan, a school located next to his alma mater, Katedralskolan, was named for him. In 1939, his portrait appeared on a series of stamps commemorating the two centuries anniversary of the founding of the Swedish Academy of Sciences.
Source of the article : Wikipedia
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