Background
Source: Wikipedia
Carl Wilhelm Scheele (German: [ˈʃeːlə], Swedish: [ˈɧêːlɛ]; 9 December 1742 – 21 May 1786) was a German-Swedish pharmaceutical chemist. Scheele discovered oxygen (although Joseph Priestley published his findings first), and identified the elements molybdenum, tungsten, barium, nitrogen, and chlorine, among others. Scheele discovered organic acids tartaric, oxalic, uric, lactic, and citric, as well as hydrofluoric, hydrocyanic, and arsenic acids.
