Wednesday, March 30, 2011

Robert Bunsen and Gustav Kirchoff

Robert Bunsen (centrum),
  Gustav Kirchhoff (odešel) a
Sir Henry Roscoe (pravý) u
Manchester univerzita v 1862
Gustav Kirchhoff (left) and Robert Bunsen (right)
Kirchoff (left) and Bunsen. Reproduced courtesy of the Library and Information Centre, The Royal Society of Chemistry.

Robert Bunsen and Gustav Kirchoff

In 1861 Bunsen and Kirchoff jointly discovered caesium (which gave a blue flame) and rubidium (which gave a red flame). Bunsen (who devised, or at least developed, the Bunsen burner) discovered only two elements himself, along with Kirchoff, but his technique was used to discover several more.

Robert Bunsen

Paul Emile Lecoq de Boisbaudran (1838 - 1912) used flame colours (called emission spectra) to search for more elements. He discovered gallium (1875), samarium and dysprosium. Gallium was the first element to be found whose properties matched elements predicted in detail by Mendeleev in 1870, dramatic proof of his ideas about the Periodic Table.