by whom?
It was discovered independently by Carl Wilhelm Scheele, in Uppsala, in 1773
Oxygen
Oxygen was isolated by Michael Sendivogius before 1604, but it is commonly believed that the element was discovered independently by Carl Wilhelm Scheele, in Uppsala, in 1773 or earlier, and Joseph Priestley in Wiltshire, in 1774
where does most of the oxygen come from on earth The most amount of Oxygen comes from photosynthesis, which uses the energy of sunlight to produce oxygen from water and carbon dioxide. when was it discovered? In the year 1773.
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Oxygen [SEP] Introduction
Another form (allotrope) of oxygen, ozone (), strongly absorbs ultraviolet UVB radiation and the high-altitude ozone layer helps protect the biosphere from ultraviolet radiation. However, ozone present at the surface is a byproduct of smog and thus a pollutant. Oxygen was isolated by Michael Sendivogius before 1604, but it is commonly believed that the element was discovered independently by Carl Wilhelm Scheele, in Uppsala, in 1773 or earlier, and Joseph Priestley in Wiltshire, in 1774. Priority is often given for Priestley because his work was published first. Priestley, however, called oxygen "dephlogisticated air", and did not recognize it as a chemical element.