Classification of a substance
Are there any substance that can exist in all three of the
states of matter at the same time? If so what is its classification name?
Water...put a piece of ice in a hot frying pan. You'll see
a solid liquid and gas of the same substance right before your eyes.
That's one off the top of my head...I'll see about any more. I don't
Know what you mean by classification, though. E-mail me with more info
if you like. Solid carbon dioxide (dry ice) almost qualifies, but
it never gets to the liquid phase since it sublimes (s--->g).
For most substances, there is a particular temperature and
pressure at which all three states (gas, solid, liquid) exist in
equilibrium. This is called the triple point on a phase diagram.
(A phase diagram of a substance simply gives the stable phase of a
substance as a function of the temperature and pressure.) The triple
point of water occurs at 0.01 degrees C and 0.006 atm. Also, please
remember that you CANNOT see water as a gas... When you see "steam"
you are really seeing small droplets of water in the liquid phase.
Water in the gas phase is colorless. -Certainly, if I drink a glass of
ice water (with ice cubes in the water on my deck here in "humid Florida" -
all three states of water are present (not in equilibrium) - but I only
see the two states (solid and liquid).
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Update: June 2012