Related Directory Categories
- Melt-Banana (3)
Sources
Help build the largest human-edited directory on the web.
Submit a site - Become an editor
Wikipedia. Licensed under the GNU Free Documentation License.
Are you an expert in this subject? Join the discussion and share your knowledge at Wikipedia.org.
Melting
From Wikipedia, the free encyclopedia
 |
This article does not cite any references or sources. (July 2007) Please help improve this article by adding citations to reliable sources. Unverifiable material may be challenged and removed. |
| Mechanical failure modes | |
|---|---|
| Buckling | |
| Corrosion | |
| Creep | |
| Fatigue | |
| Fracture | |
| Melting | |
| Rupture | |
| Thermal shock | |
| Wear | |
| Yielding | |
Melting is a process that results in the phase change of a substance from a solid to a liquid. The internal energy of a solid substance is increased (typically by the application of heat) to a specific temperature (called the melting point) at which it changes to the liquid phase. An object that has melted completely is molten.
The melting point of a substance is equal to freezing point.
Contents |
When the internal energy of a gas is increased by the application of an external energy source, the molecular vibrations of the substance increases. As these vibrations increase, the substance becomes more and more ordered.
Substances melt at a constant temperature, the melting point. Further increases in temperature (even with continued application of energy) do not occur until the substance is molten.
From a thermodynamics point of view, at the melting point the change in Gibbs free energy (ΔG) of the Material is zero, because the enthalpy (H) and the entropy (S) of the material are increasing (ΔH,ΔS > 0). Melting phenomenon happens when the Gibbs free energy of the liquid becomes lower than the solid for that material. At various pressures this happens at a specific temperature. It can also be shown that:
The "T","ΔS", and "ΔH" in the above are respectively the temperature at the melting point, change of entropy of melting, and the change of enthalpy of melting.
- Kleinert, Hagen, Gauge Fields in Condensed Matter, Vol. II, "STRESSES AND DEFECTS; Differential Geometry, Crystal Melting", pp. 743-1456, World Scientific (Singapore, 1989); Paperback ISBN 9971-5-0210-0 (readable online here)
In genetics, melting DNA means to separate the double-stranded DNA into two single strands by heating or the use of chemicals.
- See also : Polymerase chain reaction
-
From To Solid Liquid Gas Plasma Solid Solid-Solid Transformation Melting Sublimation - Liquid Freezing N/A Boiling/Evaporation - Gas Deposition Condensation N/A Ionization Plasma - - Recombination/Deionization N/A
 |
This physics-related article is a stub. You can help Wikipedia by expanding it. |