Reference Terms
from Wikipedia, the free encyclopedia


Oxygen is a chemical element in the periodic table.

It has the symbol O and atomic number 8.

The element is the most common on Earth, composing around 46% of the mass of Earth's crust, and is the third most common element in the universe.

Oxygen is a major component of air, produced by plants during photosynthesis.

Note:   The above text is excerpted from the Wikipedia article "Oxygen", which has been released under the GNU Free Documentation License.
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