Answer:
Oxygen was discovered independently by two chemists in the late 18th century: Carl Wilhelm Scheele and Joseph Priestley.
Carl Wilhelm Scheele was a Swedish chemist who is credited with the discovery of several elements, including oxygen, chlorine, and molybdenum. He was born on December 9, 1742, in Stralsund, Sweden, and showed an early interest in chemistry. In the 1770s, he made several important discoveries related to oxygen, including the fact that it is a gas and that it is necessary for combustion. However, he did not publish his findings until after Priestley had published his own work on oxygen. Scheele died on May 21, 1786, at the age of 43.
Joseph Priestley was an English scientist, philosopher, and theologian who is best known for his discovery of oxygen. He was born on March 13, 1733, in Birstall, England, and studied theology and science at the University of Leeds. In the 1770s, he conducted a series of experiments in which he isolated and described oxygen. He published his findings in 1774, in a book called "Experiments and Observations on Different Kinds of Air." Priestley's work on oxygen helped to lay the foundations for modern chemistry and the understanding of combustion and respiration. He died on February 6, 1804, at the age of 70.