< /yœns ˈyɑ kɔp/, Baron,1779–1848, Swedish chemist.
- Baron Jöns Jakob (ˈjœns ˈjɑːkɔp). 1779–1848, Swedish chemist, who invented the present system of chemical symbols and formulas, discovered several elements, and determined the atomic and molecular weight of many substances
- Swedish chemist who is regarded as one of the founders of modern chemistry. Berzelius developed the concepts of the ion and of ionic compounds and made extensive determinations of atomic weights. In 1811 he introduced the classical system of chemical symbols, in which the names of elements are identified by one or two letters.