Robert Bunsen (1811 - 1899) was a German chemist and one of the leading experimentalists of the nineteenth century. Working with the physicist Gustav Kirchhoff, he helped establish spectrum analysis as a method of chemical identification and used it to discover the elements caesium and rubidium. [1] His name endures in the Bunsen burner, a gas laboratory burner refined in his Heidelberg laboratory that became standard equipment worldwide. [3]
Early life and education
Robert Wilhelm Bunsen was born on 30 March 1811 in Göttingen, in the Kingdom of Hanover. [1] He studied at the University of Göttingen, where he took a doctorate in chemistry in 1831, and continued his training through study travels that took him to Berlin, Vienna, and Paris, where he met leading scientists and inspected laboratories and manufacturing works. [2] He began his academic career as a lecturer at Göttingen before moving through professorships at Kassel, Marburg, and Breslau.
Early research and gas analysis
Bunsen's early investigations centred on the organoarsenic compounds known as the cacodyls, dangerous substances whose study cost him the sight of one eye in a laboratory explosion and nearly killed him through arsenic poisoning. [1] From this work he showed that freshly prepared iron oxide hydrate acts as an antidote to arsenic, a remedy still cited long afterwards. [2] He also developed precise methods of gas analysis, gathered in an influential treatise, and devised the Bunsen carbon-zinc battery.
Spectroscopy and new elements
In 1852 Bunsen accepted a professorship at the University of Heidelberg, where he did his most celebrated work. [2] With his colleague Gustav Kirchhoff he built a spectroscope and demonstrated that each chemical element, when heated to incandescence, emits light at characteristic wavelengths. [1] Applying this principle of spectrum analysis, the pair identified two previously unknown elements: caesium, named for the blue lines in its spectrum, in 1860, and rubidium, named for its red lines, in 1861. [1]
The Bunsen burner and later years
To provide a clean, hot, non-luminous flame for such work, Bunsen and his instrument maker Peter Desaga improved an existing design into the burner that bears his name. [3] Bunsen also studied photochemistry with the English chemist Henry Roscoe, work that led to the Bunsen–Roscoe reciprocity law of light exposure. [2] A dedicated teacher who trained a generation of chemists, he received the Copley and Davy Medals of the Royal Society among other honours. [1] Bunsen died in Heidelberg on 16 August 1899.
