Gas

Gas is one of the states of matter. A substance becomes a gas after it reaches its boiling point as a liquid. Extreme heat can then convert a gas into a plasma. To many humanoid species the most important gases are oxygen and nitrogen, which are required for a breathable atmosphere. 
==Gases==
* Anesthezine 
* Carbon dioxide 
* Chlorine 
* Fluorine 
* Nitrogen 
* Oxygen 
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Category:Physics