31 March 1811, Göttingen (Kingdom of Westphalia) - 16 August 1899, Heidelberg (German Empire)
Robert Wilhelm Bunsen, son of Christian Bunsen, librarian and professor of literature, and Melanie Heldberg, who came from a family of librarians, studied in his hometown and obtained a doctorate in chemistry.
From 1830 onwards, he travelled between Paris (France), Vienna (Austria), and Berlin (Germany), thanks to a scholarship granted by the state government of Göttingen, establishing contact with the greatest chemists of his time.
In 1834 he took up a position at the University of Göttingen and studied metallic salts, which allowed him to make his first discovery, hydartylated iron oxide, which turned out to be an antidote still used against arsenic poisoning.
In 1836, he succeeded Friedrich Wöhler as Professor of Chemistry at the Kassel Polytechnic, but left the post two years later to go to work at the University of Marburg, where he made important advances in the field of organic chemistry, studying in depth the cacodyl compounds, which are flammable organometallic compounds with an unpleasant, garlic-like, poisonous smell, which were later presented in his book ‘Studies of the Cacodyl Series’. One of his experiments ends with a loud explosion that causes him to lose an eye.
Bunsen became interested in blast furnaces and tried to optimise their efficiency by recycling gases and utilising by-products.
In 1841, he perfected William Robert Grove's Grove battery by replacing the platinum electrode with a carbon electrode. This battery, named after him, was further improved by Georges Leclanché (Leclanché battery). In the same year, he wrote "Memoirs on batteries" and worked on a method that enabled him to separate metals by electrodeposition.
In 1852, after a brief stay in Wroclaw, he succeeded Leopold Gmelin as professor of chemistry at the University of Heidelberg, a position he held until his death.
During this period, he concentrated on the improvement of batteries, which enabled him to prepare various metals by electrolysis: aluminium, barium, calcium, chromium, lithium, magnesium, manganese, and sodium, and he invented and developed an ice calorimeter with which he could determine the specific heat of these metals and thus their atomic mass.
He also founded an important and renowned school of chemists and physicists with such outstanding students as Lothar Meyer and Dmitri Mendeléyev.
He became involved in the study of chemistry and participated in the development of what is now known as the Bunsen burner, an improvement on the burner developed by Michael Faraday. After discovering with his burner that certain substances exposed to heat gave off different shades, he decided to devote himself to the study of spectroscopy (interaction between matter and radiated energy), developing, together with Gustav Kirchhoff, the introduction of the primsa to display the spectrum and developing the first spectroscope in 1860. In 1861, together with Kirchhoff, he put forward the theory of spectral analysis, thanks to which they discovered caesium (1860) and rubidium (1861). After numerous attempts, he was unable to isolate caesium, which was obtained by electrolysis of molten salts by Carl Setterberg.
His spectroscopic work led to the later discovery of other elements such as thallium, gallium, indium, scandium, and helium.
Bunsen spent his later years enjoying the study of geology. At the time of the eruption of Mount Hekla, he made a trip to Iceland financed by the Danish government, on which Iceland depended at the time, and analysed the functioning of geysers and made a model in his laboratory to convince his contemporaries, who believed that their water came from the centre of the Earth.
He died in Heidelberg on 16 August 1899 at the age of 88.
