oxygen

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How much air do you breathe in a lifetime?

Explore an interactive periodic table of the elements

explosion limits

abundance of oxygen

Figure 10: Schematic view of ozone chemistry in a pure oxygen environment.

polar covalent bond

cryogenic region

Figure 1: Schematic diagram of a zirconia oxygen sensor used to monitor automobile exhaust gases. The sensor, approximately the size of a spark plug, is fitted into the exhaust manifold of an automobile engine. The thimble-shaped zirconia sensor, sandwiched between thin layers of porous platinum, is exposed on its interior to outside air and on its exterior to exhaust gas passing through slits in the sensor shield. The two platinum surfaces serve as electrodes, conducting a voltage across the zirconia that varies according to the difference in oxygen content between the exhaust gas and the outside air.

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oxygen: Facts & Related Content

Written and fact-checked by The Information Architects of Encyclopaedia Britannica

News •

First bacteria used oxygen one billion years earlier than we thought • Apr. 7, 2025, 6:01 AM ET (Earth.com)

Scientists Detect 'Unexpected' Oxygen in the Most Distant Galaxy Ever Found, Defying Ideas About the Early Universe • Mar. 25, 2025, 6:46 AM ET (Smithsonian Magazine)

Facts

Also Known As	O

Photos and Videos

explosion limits

abundance of oxygen

Figure 10: Schematic view of ozone chemistry in a pure oxygen environment.

polar covalent bond

cryogenic region

Figure 1: Schematic diagram of a zirconia oxygen sensor used to monitor automobile exhaust gases. The sensor, approximately the size of a spark plug, is fitted into the exhaust manifold of an automobile engine. The thimble-shaped zirconia sensor, sandwiched between thin layers of porous platinum, is exposed on its interior to outside air and on its exterior to exhaust gas passing through slits in the sensor shield. The two platinum surfaces serve as electrodes, conducting a voltage across the zirconia that varies according to the difference in oxygen content between the exhaust gas and the outside air.

How much air do you breathe in a lifetime?

Understand the carbon and oxygen cycles in the atmosphere

How a candle flame burns

How light affects plant growth

The relationship between photosynthesis and breathing

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Topics

ozone liquid oxygen oxygen-16 oxygen-17 oxygen-18 hypoxia air nitric acid oxygen cycle biogenic gas hydrogen carbon sodium nitrogen sulfur phosphorus boron iodine fluorine zinc

Dig Deeper: More Articles That Discuss This Topic

Key People

Carl von Linde

Carl von Linde

German engineer

Antoine Lavoisier

Antoine Lavoisier

French chemist

Joseph Priestley

Joseph Priestley

English clergyman and scientist

German Swedish chemist Carl Wilhelm Scheele, c. 1780.

Carl Wilhelm Scheele

Swedish chemist

Mayow, detail of an engraving

John Mayow

English chemist and physiologist

Quiz

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List

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