Jöns Jacob Berzelius

Swedish chemist

• Born: August 20, 1779; Väversunda, Sweden
• Died: August 7, 1848; Stockholm, Sweden

Born in the eighteenth century and working in the nineteenth, Jöns Jacob Berzelius was a Swedish chemist best known for his work in chemical notation and atomic weights. He was also an early investigator in the field of organic chemistry.

Primary field: Chemistry

Specialties: Physical chemistry; organic chemistry

Early Life

Jöns Jacob Berzelius (ber-zee-lee-UHS) was born in Väversunda, Sweden, on August 20, 1779. His father was a clergyman and schoolmaster who died when Berzelius was four. His mother remarried and died when he was eight. Berzelius was educated first at a local, academically renowned school in Linköping. In 1796, he began his studies in medicine at Uppsala University. He left school to work as a pharmacist when his scholarship was withdrawn. When he earned enough money, he returned to school and received his doctorate in 1802 for work on the influence of electricity, in the form of galvanic current, upon disease. Galvanic current was DC (direct current) derived from voltaic piles, an early form of the battery. He found nothing new; however, the experience cemented his long-standing interest in electricity. It was during his studies at Uppsala that he was introduced to chemistry by his stepbrother. The two had a chemistry textbook that they read through together, also doing several of the experiments. After working for a time as a doctor, he served as a professor of medicine and pharmacy at the Karolinska Institute, sometimes called the Stockholm Institute of Medicine, in Stockholm in 1807. Although the position did not pay, it provided a means to continue his experiments in chemistry. In 1808, he was elected to the Royal Swedish Academy of Sciences. From 1818 onward, he would serve as its perpetual secretary. That same year, as a result of his increased international recognition, he was awarded a title of nobility by the Swedish king.

Life’s Work

In 1806 Berzelius published the first edition of his chemistry textbook, which would later be translated into six languages and become the standard textbook for chemistry for the next fifty years.

Upon hearing about English chemist John Dalton’s work in identifying the atomic weight of elements around 1807, Berzelius was inspired to participate in the work. By 1818, he had obtained accurate figures for the atomic weight of forty-five elements. While doing this work, he found that referring to each element by its full name was counterproductive and that Dalton’s system of standardized pictographs derived from alchemy was unwieldy. As a result, Berzelius created his own system of abbreviations for elements based on their Latin names. His system is still in use today.

In addition to this work with elements, Berzelius also performed experiments using electricity supplied from voltaic piles, a form of early batteries. He did some of these experiments with his friend Wilhelm Hisinger. Early results included the discovery that solutions of salts could be separated by electric current. In later experiments, he found that he could produce amalgams of potassium, ammonia, and calcium by using mercury as a negative electrode. These experiments lead to a friendship with Sir Humphry Davy, a prominent English scientist of the time.

From these experiments, Berzelius developed an electrochemical theory, figuring that all compounds were composed of and could be separated into positive and negative components. This theory became popular in mineralogical circles.

From all of this work, he helped prove the law of definite proportions, which states that all compounds are composed of atoms in whole numbers. Thus, for example, there can be no half atoms of oxygen. Additionally, he disproved English chemist William Proust’s hypothesis that all elements were composed of different amounts of hydrogen atoms. Thus, iron has an atomic mass number of fifty-six but weighs a bit less than fifty-six hydrogen atoms because of the energy lost in fusing the atoms together in stars. Proust’s hypothesis remained controversial throughout the period and was not fully resolved until much later, with the discovery of isotopes.

At the same time, starting in 1807, as part of his work at his laboratory, he began research in the field that is now called organic chemistry. After studying the brain, he turned to analyzing animal substances. These included blood, digestive fluids, milk, muscles, fats, membranes, and all manner of other things to be found in animals. He found that blood contains iron and that muscular tissue contains lactic acid, also found in sour milk. As he was the first to admit, much of his work was inconclusive and required further advances in equipment and technique. However, this latter discovery led to major breakthroughs later on.

As his career continued, Berzelius would make other major discoveries in chemistry. In 1818, he discovered the element selenium, naming it for the moon. In 1821, he began publishing an annual review of chemical research. The final review was published in 1849, a year after his death. In 1824, he discovered silicon. In 1829, he discovered thorium.

In 1831, after hearing of many cases in which compounds had identical constituents—an identical chemical formula but different properties—and remembering back to his own experience with lactic acid in which the version in muscle tissue reacted differently to polarized light than did that resulting from fermentation, Berzelius suggested the concept of isomerism. This means that two or more chemicals share an identical formula, but have atoms arranged in different structures. This is particularly important in organic chemistry. For example, many of the molecules in the body have a property called chirality, or handedness. The two versions of the molecule are identical, except that they are reversed in orientation.

In 1832, Berzelius resigned from the university to concentrate on his work for the academy. In 1835, he came up with the idea of catalysts, the idea that the presence of certain chemicals might change how other chemicals interact, making it easier for them to react. That same year, he married Elisabeth Poppius and was made a baron by King Charles XIV. In 1836, he was awarded the Copley Medal by the Royal Society of London. Berzelius died on August 7, 1848, an authority on chemistry.

Impact

Berzelius is one of the founders of modern chemistry. As a proponent of Enlightenment-era logic in the romantic era, he helped continue the work of science. He established much of the notation still used today for chemistry. These tools allowed for greater systemization of the study, making it easier for chemists to organize and share their findings. Everyone who does any kind of work in chemistry uses the system; the lack of major changes to it throughout history is a testament to its simplicity and elegance. Berzelius’s table of atomic masses also served as a source of extremely accurate figures for chemical experimentation during the nineteenth century. His numbers played a significant role in those discoveries, which is all the more remarkable, given that he was working before the advent of atomic theory.

His work also provided critical evidence for the nature of chemical compounds, proving the law of whole ratios (that there are no half-atoms in compounds and that compounds are not composed solely of repeated hydrogen atoms).

Equally, his work in biochemistry, while occurring too early in the history of the field to have produced any conclusive data, had far-reaching consequences. The concepts of isomerism and catalysis that Berzelius researched became vitally important to chemistry.

Bibliography

Dominiczak, M. H. “Berzelius, Liebig, and the Infrastructure of Chemistry.” Clinical Chemistry. 57.10 (2011): 1468–70. Print. Traces the work done by Berzelius in the field of chemical notation, including the terms he introduced and his work with chemical formula notation.

Scerri, Eric R. The Periodic Table: A Very Short Introduction. Oxford: Oxford UP, 2011. Print. A fresh look at the periodic table of elements, including a discussion of the arrangements of the elements in the table, as well as notes on the fields of atomic physics and quantum mechanics.

Trofast, Jan. A Tribute to the Memory of Jacob Berzelius (1779–1848): Presented at the 2006 Annual Meeting of the Royal Swedish Academy of Engineering Sciences. Stockholm: Royal Swedish Academy of Engineering Sciences, 2006. Print. Presents a tribute to Berzelius’s contributions and discoveries, including chapters on the importance and implications of his work.

---. “Berzelius’s Discovery of Selenium.” Chemistry International. 33.5 (2011): 16–19. Print. Details the work that led to Berzelius’s discovery of selenium, also discussing the implications of this finding.