Reference Terms
from Wikipedia, the free encyclopedia


Hydrogen is a chemical element in the periodic table that has the symbol H and atomic number 1.

At standard temperature and pressure it is a colorless, odorless, nonmetallic, univalent, tasteless, highly flammable diatomic gas.

However, in extremely cold and dense environments, hydrogen can be metallic.

Hydrogen is the lightest and most abundant element in the universe.

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