Carl Wilhelm Scheele

Birth: December 9, 1742
Death: May 21, 1786
Nationality: German-Swedish
Occupations: He was an apprentice since he was fourteen-years-old for eight years before becoming an apothecary's clerk.
How the element oxygen was discovered: Beforing studying oxygen Scheele studied air. He found that air was a mixture of "fire air" and "foul air" which means it is a mixture of two gases. He found that oxygen was the combustible gas.
Other accomplishments: Discovered molybdenum, tungsten, and chlorine