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. C

    What happen to the kinetic and potential energy during the boiling and melting?

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  2. J

    Confusion over melting & crystallization?

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  3. P

    Decrease in Aspirin Melting Point

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  4. N

    Thermodynamics, melting, phase change

    Homework Statement If ice is at(-12) deg c and has a mass of .55593125kg, how much heat is required to melt the ice. Homework Equations Q=mcT The Attempt at a Solution i tried Q=mc(water)T and Q=mc(ice)T but both were marked wrong. can you show me what I am doing wrong here?
  5. Z

    Boiling Point before Melting Point?

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  6. N

    Why is melting called fusion ?

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  7. H

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  8. D

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  9. W

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  10. S

    Does melting deteriorate the crystalline order?

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  11. A

    Cool Coffee with Melting Ice Cube: Solve for T

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  12. N

    Melting ice block on an inclined plane?

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  13. P

    Calculate melting point of ice under pressure

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  14. E

    Is Melting Tyvek Safe? Bonding for Projects

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  15. S

    Relationship between Interaction Energy and Melting Temperature

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  16. H

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  17. H

    Fluid Mechanics : Ice cube melting and Surface Energy Que.

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  18. C

    Salt Melting Ice: Heat & Cooling Effects

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  19. Y

    Why impurities decrease melting points.

    anyone tell me why melting points of any substance decrease when we add any other material
  20. M

    Solution to Thermo Ice Melting Problem

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  21. N

    Melting ice using latent heat and heat of fusion

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  22. I

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  23. D

    Ice melting in water in a gravity free fall

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  24. P

    How to lower melting point of solids (TiO2)?

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  25. D

    How can i keep an ce cube from melting?

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  26. J

    Thermodynamics Question- Melting Temp

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  27. L

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  28. S

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  29. S

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  30. S

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  31. S

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  32. T

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  33. G

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  34. T

    What is the melting temperature of diamond?

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  35. G

    Which Solid Has the Highest Melting Point?

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  36. M

    How Does the Presence of Impurities Affect the Melting Point of Substances?

    I have tried a quick scan of the web for general information relating to the depression of melting points and found very little available, so i started this thread. The general idea is a depression curve which will help you identify by how much a sample contains impurities. I was looking for...
  37. turbo

    Spring IR Melting: The Raspberry Cane Effect

    Here is something that I see every spring, when the sun gets higher in the sky and the temps moderate. Notice the depressions under the raspberry canes... The sun heats up the canes, both above and below (reflection from the snow) and the canes re-radiate IR, melting the snow below them, even...
  38. S

    Melting Ice: Does Water Surface Rise?

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  39. V

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  40. B

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  41. M

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  42. T

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  43. P

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  44. J

    Fluid mechanics - ice melting into water

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  45. D

    Calculating Heat, U, G, V, & S for Melting 1 kg Ice

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  46. N

    Increasing the Melting Point via Pressure Increase

    1. What is the pressure needed to increase the melting temperature by 20 centigrade degrees? Given: Molar Volume (solid) at normal melting temp is 18.92 cm^3 Given: Molar Volume (liquid) at normal melting temp is 19.47 cm^3 Homework Equations delta H (s>l) = T(melting point)* delta S(s>l)...
  47. R

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  48. J

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  49. E

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  50. E

    Why does melting point decrease for impure solid?

    Okay, i am doing a lab involving crude acetaminophen and pure acetaminophen. The crude acetaminophen is supposed to have a lower melting point than the pure acetaminophen... how does that work and why? does it have to do with thermodynamics or what??
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