Gas

Gas is one of the four fundamental states of matter (the others being solid, liquid, and plasma). A pure gas may be made up of individual atoms (e.g. a noble gas or atomic gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or compound molecules made from a variety of atoms (e.g. carbon dioxide). A gas mixture would contain a variety of pure gases much like the air. What distinguishes a gas from liquids and solids is the vast separation of the individual gas particles. This separation usually makes a colorless gas invisible to the human observer. The interaction of gas particles in the presence of electric and gravitational fields are considered negligible as indicated by the constant velocity vectors in the image.

The gaseous state of matter is found between the liquid and plasma states, the latter of which provides the upper temperature boundary for gases. Bounding the lower end of the temperature scale lie degenerative quantum gases which are gaining increasing attention. High-density atomic gases super cooled to incredibly low temperatures are classified by their statistical behavior as either a Bose gas or a Fermi gas. For a comprehensive listing of these exotic states of matter see list of states of matter.

Read more about Gas:  Elemental Gases, Etymology, Physical Characteristics, Macroscopic, Microscopic, Simplified Models, See Also

Famous quotes containing the word gas:

    one pale woman all alone,
    The daylight kissing her wan hair,
    Loitered beneath the gas lamps’ flare,
    With lips of flame and heart of stone.
    Oscar Wilde (1854–1900)

    A new father quickly learns that his child invariably comes to the bathroom at precisely the times when he’s in there, as if he needed company. The only way for this father to be certain of bathroom privacy is to shave at the gas station.
    Bill Cosby (20th century)

    Droning a drowsy syncopated tune,
    Rocking back and forth to a mellow croon,
    I heard a Negro play.

    Down on Lenox Avenue the other night
    By the pale dull pallor of an old gas light
    Langston Hughes (1902–1967)