What is Melting: Definition and 274 Discussions

Melting, or fusion, is a physical process that results in the phase transition of a substance from a solid to a liquid. This occurs when the internal energy of the solid increases, typically by the application of heat or pressure, which increases the substance's temperature to the melting point. At the melting point, the ordering of ions or molecules in the solid breaks down to a less ordered state, and the solid "melts" to become a liquid.
Substances in the molten state generally have reduced viscosity as the temperature increases. An exception to this principle is the element sulfur, whose viscosity increases in the range of 160 °C to 180 °C due to polymerization.Some organic compounds melt through mesophases, states of partial order between solid and liquid.

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  1. R

    Exploring Heat Differences in Ice Melting in 2 Cylindrical Containers

    Hello everyone! I recently saw a problem about some ice in 2 containers. So: We have 2 vertical cylindrical containers, which have perfect insulating walls, one with surface of the base S and the other one 2S , filled with the same mass of ice. The question is if there is any diffrence between...
  2. A

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    When an ice melts on water, which was initially floating on it, the water level must get increased. Why it remains unchanged??
  3. Mike Dacre

    Mixed Melting Point of Two Pure Solid Crystals

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  4. DustinSmith

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  5. Mnemonic

    Thermodynamics relating to temperature and phase changes V.2

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  6. Borek

    Melting Nickel Ball: Temperature & Radius Effects

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  7. B

    Connection between increase in pressure and melting point

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  8. B

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  9. mss90

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  10. M

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  11. J

    Aluminum structure modifications for use near a very hot fire

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  12. Robsta

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  13. F

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  14. INFINITE952

    What material has the lowest melting point?

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  15. KingCrimson

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  16. C

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  17. T

    List compounds in order of increasing melting point

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  18. skyshrimp

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  19. K

    Velma and Mort's ice cream is melting special relativity problem. Help please.

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  20. H

    Explaining Pressure: Boiling & Melting Point Changes

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  21. F

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  22. F

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  23. Art_Vandelay

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  24. C

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  25. B

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  26. D

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  27. D

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  28. D

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  29. Y

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  30. R

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  31. E

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  32. Q

    Understanding Phase Diagrams: Boiling, Melting & Critical Points

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  33. S

    Why does melting and boiling occur at a specific temperature?

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  34. D

    Very quick question regarding melting point and purity

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  35. W

    Thermal intake of melting ice as compared to thermal capacity of earth

    Though this topic mentions climate change, I don't think it really is about it that, strongly anyway. I've just joined and noticed a ban on climate change discussions before posing this one, I don't think this is one, but if it is, I suppose the beast must have one of it's many heads chopped...
  36. C

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  37. A

    Why does the melting point of graphite is higher than diamond?

    In diamond valence electrons are fully covalently bonded.But in graphite only three are covalently bonded while one electron is freely moving.So it seem that melting point of diamond should be higher than that of graphite because in diamond we should break four covalent bonds while in graphite...
  38. M

    Why A Silica Powder Is Melting But Not Burnt When Heated?

    Why a silica powder is melting but not burnt when heated? Thank you
  39. A

    Melting Plastics: Exploring Outcomes of Trawling Ocean Garbage Patches

    What would happen if I trawled one of the oceans garbage patches (say the great pacific or atlantic garbage patches) and put everything I trawled into a furnace with an inert gas hot enough to melt the majority of plastics I picked up, what would be the outcome? I am looking to know more...
  40. T

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  41. R

    Melting Points as Function of P

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  42. K

    Time for melting and vaporising a wax candle

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  43. B

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    I'm currently looking into some dental material mechanics. Material: Pressable ceramic powder Melting range: 900-1000°C If I were to heat it up to approx 1200°C, what would happen to it? Would it still be just molten form of the material? Student
  44. W

    Melting and recasting pure iron bars?

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  45. A

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  46. A

    How Does Gibbs Free Energy Relate to Phase Changes?

    Hi, As I understand, during the process of phase change from a liquid to solid (or any phase change for that matter,) the temperature of the substance remains constant as the energy being applied to the substance is used in changing phase. How does this relate to Gibbs free energy? I read that...
  47. D

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  48. Q

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  49. P

    Melting Ice in Seawater: Cooling Steel on Seabed with 30kg Ice Block at -20degC

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  50. J

    Counter intuitive melting temperatures

    I have heard that the melting/freezing point of helium is lower than that of hydrogen. Is this correct? if so why? My thoughts on this are that hydrogen has the lowest mass and therefore requires less energy than helium to be in a liquid or gaseous state, so it appears counter intuitive that...
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