Berzelius, J�ns Jacob 1779-1848
Swedish chemist

Born in V�fversunda, East G�tland, he studied medicine at Uppsala and worked as an unpaid assistant in the College of Medicine at Stockholm before succeeding to the chair of medicine and pharmacy in 1807. In 1815 he was appointed Professor of Chemistry at the Royal Caroline Medico-Chirurgical Institute in Stockholm, retiring in 1832. Soon after Alessandro Volta's invention of the electric battery, Berzelius began in 1802 to experiment with the voltaic pile. Working with Wilhelm Hisinger he discovered that all salts are decomposed by electricity. He went on to suggest that all compounds are made up of positive and negative components, a theory which laid the foundations for our understanding of radicals. In 1803 he and Hisinger discovered cerium; Berzelius also discovered selenium and thorium and was the first person to isolate silicon, zirconium and titanium. His greatest achievement, however, was his contribution to atomic theory. Matching the idea of constant proportions with John Dalton's atomic theory, and persuaded of the central importance of oxygen from his studies of Antoine Lavoisier's work, he drew up a table of atomic weights using oxygen as a base, devising the modern system of chemical symbols. He also made significant contributions to organic chemistry. A pioneer of gravimetric analysis, he has had few rivals as an experimenter. As a result of the poverty of his early years, he had to improvise much of his apparatus and some of his innovations are still standard laboratory equipment, eg wash bottles, filter paper and rubber tubing. He was elected to the Stockholm Royal Academy of Sciences in 1808 and became its secretary in 1818. He was awarded the Gold Medal of the Royal Society of London, and in 1835 he was created a baron by Charles XIV.

Bibliography: Hans Krook, Jacob Berzelius (1979)