what are it's uses?
Low Pressure Breathing gas in Modern Space Suits, Scuba Divers rely on artificially delivered Oxygen & Medically for Oxygen Masks among many other uses.
Oxygen
An application of as a low-pressure breathing gas is in modern space suits, which surround their occupant's body with the breathing gas. These devices use nearly pure oxygen at about one-third normal pressure, resulting in a normal blood partial pressure of . This trade-off of higher oxygen concentration for lower pressure is needed to maintain suit flexibility.

Scuba and surface-supplied underwater divers and submariners also rely on artificially delivered . Submarines, submersibles and atmospheric diving suits usually operate at normal atmospheric pressure. Breathing air is scrubbed of carbon dioxide by chemical extraction and oxygen is replaced to maintain a constant partial pressure. Ambient pressure divers breathe air or gas mixtures with an oxygen fraction suited to the operating depth. Pure or nearly pure use in diving at pressures higher than atmospheric is usually limited to rebreathers, or decompression at relatively shallow depths (~6 meters depth, or less), or medical trea
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. by whom? It was discovered independently by Carl Wilhelm Scheele, in Uppsala, in 1773
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Oxygen [SEP] Life support and recreational use
An application of as a low-pressure breathing gas is in modern space suits, which surround their occupant's body with the breathing gas. These devices use nearly pure oxygen at about one-third normal pressure, resulting in a normal blood partial pressure of . This trade-off of higher oxygen concentration for lower pressure is needed to maintain suit flexibility. Scuba and surface-supplied underwater divers and submariners also rely on artificially delivered . Submarines, submersibles and atmospheric diving suits usually operate at normal atmospheric pressure. Breathing air is scrubbed of carbon dioxide by chemical extraction and oxygen is replaced to maintain a constant partial pressure.