Phases of the Elements

Under normal conditions, most of the elements exist in the solid phase.  Some, however, exist as gases or liquids.  The internal structure and the element's intermolecular forces govern the state of the element at a given temperature.
Changing the temperature alters the ability of the particles of the bulk element to overcome the forces holding them together, possibly causing the element to solidify, melt or vaporize.  In these cases, the phase of a substance is governed by competing forces. Intermolecular (or interatomic forces) arrange the substance as a liquid or solid, while thermal motions attempt to separate the particles into the gas phase.  As the temperature rises, the thermal motions of a solid substance overcome the intermolecular or interatomic forces, converting it first to a liquid and finally to a gas.  Melting points and boiling points of the elements give an indication of their relative intermolecular or interatomic forces.
This program demonstrates the effect of temperature on the phases of the elements.  As the temperature is varied, the computer generated periodic table changes color to indicate the state of each element.  The phase of each element will be denoted by the color of its box.
 
 
 

 
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Last modified: April 13, 2000