Carl Wilhelm Scheele

Lore & Background

Carl Wilhelm Scheele was a German-Swedish pharmaceutical chemist who preferred speaking German to Swedish throughout his life, as German was commonly used among Swedish pharmacists. He was born in Stralsund, in western Pomerania, then a Swedish Dominion within the Holy Roman Empire. His father was a grain dealer and brewer from a respected family. At age fourteen, Scheele was sent to Gothenburg to apprentice as a pharmacist under a family friend, Martin Andreas Bauch, a position he held for eight years. During this time, he conducted experiments late into the night and studied the works of earlier chemists, particularly Georg Ernst Stahl, whose phlogiston theory heavily influenced Scheele’s own later theoretical speculations. After working under apothecary C. M. Kjellström in Malmö, he moved to Stockholm, where he discovered tartaric acid and, with his friend Anders Jahan Retzius, studied the relationship between quicklime and calcium carbonate. He later became director of a laboratory at Uppsala, supplying chemicals to Professor Torbern Bergman, and a friendship developed after Scheele solved a reaction involving melted saltpetre and acetic acid that Bergman could not resolve. Scheele discovered oxygen, though Joseph Priestley published his findings first, and also identified the elements molybdenum, tungsten, barium, nitrogen, and chlorine. He discovered several organic acids, including tartaric, oxalic, uric, lactic, and citric, as well as hydrofluoric, hydrocyanic, and arsenic acids. Doctors attributed his death to mercury poisoning from his lifelong work as a chemist.

Reader's Guide

Scheele’s significance stems from his extensive experimental work, which yielded a remarkable number of chemical discoveries despite his lifelong commitment to the phlogiston theory. Through careful study of air, he demonstrated that it was not a single element but a mixture of two distinct gases, which he termed “fire air” and “foul air.” He isolated “fire air” by heating substances such as saltpetre, manganese dioxide, and mercuric oxide, though he interpreted this gas within phlogistical terms, believing it combined with phlogiston in materials to be released during combustion. His identification of new elements included barium, manganese, molybdenum, and tungsten, and he also isolated nitrogen and chlorine. In organic chemistry, he discovered several acids: tartaric, oxalic, uric, lactic, and citric, as well as hydrofluoric, hydrocyanic, and arsenic acids. Although his first publication on air and fire was delayed until 1777, by which time Joseph Priestley and Antoine Lavoisier had already published similar findings on oxygen, Scheele’s work was foundational. His experiments, conducted without the expensive equipment available to Lavoisier, helped generate the data that ultimately led to the abandonment of the phlogiston theory, even though Scheele himself never rejected it. His career was marked by a series of discoveries later credited to others, leading Isaac Asimov to call him “hard-luck Scheele.” He died of mercury poisoning, likely from his lifelong work as a chemist.

Did You Know?

• He identified elements including barium, manganese, molybdenum, and tungsten.
• He discovered organic acids such as tartaric, oxalic, uric, lactic, and citric.
• He discovered a process similar to pasteurization.
• Isaac Asimov called him 'hard-luck Scheele' because many of his findings were later credited to others.