Born: 9 December 1742, Stralsund, Germany
Died: 21 May 1786, Köping, Sweden

Carl Wilhelm Scheele was a German-Swedish medicinal scientist who lived from December 9, 1742, to May 21, 1786. He was a prolific scientist who faced adversity and limited resources to make plenty of major chemical discoveries. He was the first to discover and manufacture oxygen and chlorine gas. Yet, because his work was not well received by his peers, much of it had to be rediscovered. His work had a significant impact on the evolution of chemistry, despite his name not being as widely known as that of many of his contemporaries.
Biography
Scheele was born in Swedenborg, Western Pomerania, Germany, which was under Swedish administration at the time. Joachim Christian Scheele, a trader, had eleven children, and he was one of them. He began his career as a pharmacist at the age of 14 in the Gothenburg business of Martin Anders Bauch. His brother worked for Bauer as well, but he died three years before Scheele started his apprenticeship. Scheele was a student for the first six years and then worked as an assistant for three more.
During this time, he took use of Bauer’s excellent library and gained an advanced understanding of the chemistry of the day through study and practice. He is claimed to have studied at the drugstore after hours and conducted late-night experiments. He allegedly researched in the drugstore after hours, and while conducting experiments late one evening, he reportedly set off an explosion that shook the house and woke up the residents. Scheele was advised to seek work elsewhere.
He was then engaged as an apothecary’s clerk at Kalstom’s in Malmö, where he stayed for two years. Following that, he worked at Scharenberg in Stockholm. He submitted a memoir about the discovery of tartaric acid at this period, but the Swedish Academy of Sciences rejected it because he was not well-known at the time. This is said to have discouraged Scheele from contacting those who would have most appreciated his work. He would not become a member of the academy until he was thirty-three.
International reputation
Scheele began his career as a scientist while working in Stockholm. Scheele moved to Look’s shop in Uppsala in 1773 after spending six years there. During this time, he is reported to have met Torbern Olof Bergman, a notable Swedish scientist, and professor of chemistry at the University of Uppsala. Bergman was brought to the pharmacy by Scheele’s boss, who provided Bergman with his chemicals, to consult Scheele on a topic that had been troubling him.
Scheele provided a comprehensive explanation and exhibited a broad comprehension of chemical events in general. Bergman was essential in bringing Scheele’s successes to the notice of the scientific community and in having his work published, in addition to befriending him. Scheele thus began to earn an international reputation and corresponded with the likes of Henry Cavendish, of Great Britain, and Antoine Lavoisier, of France.
Later years
Scheele intended to buy a pharmacy in 1775 so that he could work on his own. His early attempts to buy a business failed, but he received numerous requests to conduct research and teach in several European cities. Scheele declined these offers, preferring to stay in a field he was familiar with and that paid well enough to cover his expenses. He was successful in purchasing a shop in Koping from Sara Margaretha Sonneman, who had inherited it from her late husband, Hinrich Pascher Pohls, after a year’s wait. Scheele discovered that the business was in debt, which he was able to pay off over time by paying close attention to his business concerns.
For the sake of economics, he and Pohls’ widow kept the house together throughout this time. Only a few days before his death, he married her. Scheele was able to pay off his new business’s whole debt and build himself a new home and laboratory. Scheele enlisted the help of one of his sisters to run the pharmacy and the household. As a result, they were able to live comfortably for the rest of Scheele’s life.
Scheele was frequently visited by scientists in the latter decade of his life, who attempted to probe his creative mind. Scheele preferred to entertain in his lab or pharmacy, and he didn’t travel much.
He suffered from gout and rheumatism but continued his scientific work up to the final month of his life. His illness was probably brought on by his constant exposure to the poisonous compounds he worked with. He died on May 21, 1786.
Accomplishments
Discovery of oxygen
Unlike other well-known scientists such as Antoine Lavoisier and Isaac Newton, Scheele had a low post in a small town and still was able to accomplish numerous scientific breakthroughs. He preferred the intimacy of his small home over the grandeur of a large home. Scheele produced many chemistry breakthroughs before others who are commonly credited. During the years 1771-1772, Scheele made a variety of experiments in which he heated substances and discovered oxygen as a by-product. Scheele, on the other hand, was not the one who named or defined oxygen; that honor went to Antoine Lavoisier.
Scheele researched air before discovering oxygen. Air was once assumed to be a non-interfering element that made up the environment in which chemical processes took place. Scheele’s research into air led him to the conclusion that it was a mixture of “fire air” and “bad air,” or oxygen and nitrogen, the former breathable and other not. He burned compounds like saltpeter (potassium nitrate), manganese dioxide, heavy metal nitrates, silver carbonate, and mercuric oxide in a variety of studies. However, it was not until 1777 that his discoveries were published in the work Chemical Treatise on Air and Fire. Both Joseph Priestley and Antoine Lavoisier had already published their results and conclusions on oxygen by that time. In his treatise, Scheele also distinguished heat transfer by thermal radiation from that by convection or conduction.
Other discoveries
Scheele is credited with being the first to discover several chemical elements, including barium (1774), manganese (1774), molybdenum (1778), and tungsten (1781), as well as several chemical compounds, including citric acid, glycerol, hydrogen cyanide (also known as prussic acid in aqueous solution), hydrogen fluoride, and hydrogen sulfide. In addition, he found a pasteurization-like technique, as well as a method of mass-producing phosphorus (1769), propelling Sweden to become one of the world’s main matchmakers. Scheele discovered the mineral color copper arsenide, later known as Scheele’s Green, in 1775. Pigments with a lower toxicity level were used to replace the chemical.
In 1774, Scheele produced another significant technological discovery, maybe even more revolutionary than his isolation of oxygen. In a specimen of pyrolusite provided to him by his friend Johann Gottlieb Gahn, he identified lime, silica, and iron, but was unable to identify an additional component. He created a yellow-green gas with a strong odor when he treated the pyrolusite with hydrochloric acid in a warm sand bath. The gas reached the bottom of an open bottle and was denser than ordinary air, he observed. He also mentioned that the gas was not water-soluble. It changed the color of corks to yellow and took the color out of wet, blue litmus paper and some flowers. He called this gas with bleaching abilities, “dephlogisticated acid of salt.” Eventually, Sir Humphry Davy named the gas chlorine.
Scheele and the phlogiston theory
Scheele had studied the main theory on gases in the 1770s, the phlogiston theory, by the time he was a teenager. Phlogiston is a “matter of fire” according to the classification system. According to the hypothesis, any material capable of burning would produce phlogiston during combustion and cease to burn after all of the phlogiston had been released. Scheele coined the term “fire air” to describe oxygen’s ability to support combustion. He described oxygen in terms of the established phlogiston theory.
Among several great scientists, including his contemporaries Antoine Lavoisier, Joseph Black, and Joseph Priestley, historians of science largely acknowledge that Scheele was the first to discover oxygen. Scheele made the discovery three years before Joseph Priestley, according to the evidence.
Priestley relied greatly on Scheele’s work, and it’s possible that he wouldn’t have discovered oxygen on his own if it hadn’t been for him. According to Lavoisier’s correspondence with Scheele, Scheele got fascinating discoveries without the modern laboratory equipment that Lavoisier used. Chemistry became a standardized field with regular processes due to the work of Lavoisier, Joseph Priestley, Scheele, and others.
Legacy
Scheele was well ahead of his time in many ways. Much of what he did had to be rediscovered since his contemporaries did not appreciate it. His discovery of chlorine gas and his understanding of radiant heat are just two examples of work that were completely overlooked and had to be rediscovered by others. He found oxygen before Priestley and Lavoisier, and this discovery was a critical step in disproving the long-held phlogiston theory. He made significant contributions to organic chemistry, an area that would not be developed for another 40 years after his death. Scheele is regarded as a pioneer in the field of analytical chemistry. All of this was done with very little equipment, the majority of which he designed himself.
Although many of his discoveries are credited to others, and his name is not as well known as that of many of his contemporaries, his contributions to chemistry were significant and had a significant impact on its evolution.