Fusion

Cup by the snow, which melts

Fusion ( Latin : Liquefactio): is the process that leads to change phases of a substance from the solid phase to a liquid phase . Increase the internal energy of the solid phase (usually by the application of heat) to a certain temperature (called the melting point ), which then turns to liquid phase . The so-called body that completely melted Mounsr . Fusion occurs when the temperature at which exists then the solid phase and the liquid of the pure substance in equilibrium . When you reach the point of fusion will result in more heat to the steel body is gradually turning into a liquid without a change in temperature , but during this case gets to the so-called heat of fusion. Melting point and heat of fusion of the two special properties of the material . Melting temperature Madend melt all the solid material , the extra heat will raise the temperature of the liquid .

Example : the snow melts at a temperature of 0 ° C , and its melting temperature is equal to 333.500 MJ / kg. That heat is needed to convert 1 kg of ice to water . During the transition temperature stays constant at zero percentile until all the snow turned to water .

Melting point of the crystalline solid material is characteristic of the material, and used to identify vehicles and pure elements . Most of the mixtures and non- crystalline objects ( = Omorvih be Nusia atoms which randomly without regulation ) fused within the field of temperatures.

Is the melting point of the solid material is generally the same as the freezing point of the liquid material . The freezes the liquid crystal according to several different systems , and because the impurities lower the freezing temperature , the reality dictates that the freezing temperature is not equal to the temperature of fusion. And thus to identify the article are resorting to fusion temperature . For example , you need to nuclei of water crystals begin to form around the crystals . The water in a clean cup will cool down to several degrees below the freezing point without freezes .

From the viewpoint of thermodynamics , the change in Gibbs free energy of the material at the point of fusion is equal to zero , because of the increased enthalpy (H) and entropy (S) A (ΔH, ΔS> 0). Fusion phenomenon occurs when the Gibbs free energy of the liquid is lower than the case of solid state . And at a variety of pressures , this occurs at a specific temperature . It can also be :

\ Delta S = \ frac {\ Delta H} {T}

Where "T", "\ Delta S", and "\ Delta H". Are , respectively, the temperature at the point of fusion , the change in Antorpa fusion , the change in the fusion warmers

Melting solid

When we heat the solid material is pure temperature begins to rise until it reaches the melting point and turning the heat absorbed by the body into liquid steel . During that period the temperature of the system remain fixed until the turn of each of the solid to a liquid state ( phase transition ) . After turning each piece of solid material into a liquid temperature of the liquid begins to increase with continued heating. And continues to rise in the temperature of the liquid to continue heating until it reaches a temperature to the boiling point , and then starts the liquid turns into a vapor . This is also the last phase shift .

During the process of evaporation system temperature remains constant. For example, for the water temperature of the water remains , which boiled fixed at a temperature of 100 ° C until all the water turns to steam . In the meantime, stores steam heat gained during its transformation from a liquid state to a gaseous state developed in the form of latent heat .

The amount of heat required for melting a substance called Anthalbe melting temperature or fusion or latent heat of fusion , which is measured in J / Mall , or measured in J / kg.

The graph shows the change in temperature ( vertical axis ) of the solid with the heating time ( horizontal axis ) . We consider the stability of the temperature at turning solid material into a liquid , as well as the stability of the temperature at boiling point during the transformation of liquid to vapor .

Fusion is not compatible

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Fusion is compatible (in English : Incongruent melting) is the dilute solid socializing disintegration of solid material or interaction with the molten material to give a solid and developed other means Petrkibhma differ from the original solid material . For example , material Enstatite (Enstatite), a magnesium silicate MgSiO3, fused are not compatible at low pressure to form Vorstrajt (Forsterite) , which is another type of magnesium silicate Mg2SiO4, means rich silica SiO2. When pressure ranges between 2.5 and 5.5 GPa , it becomes a melting Alanstadtaat compatible .

Fusion is compatible (in English : Incongruent melting) is the dilute solid socializing disintegration of solid material or interaction with the molten material to give a solid and developed other means Petrkibhma differ from the original solid material . For example , material Enstatite (Enstatite), a magnesium silicate MgSiO3, fused are not compatible at low pressure to form Vorstrajt (Forsterite) , which is another type of magnesium silicate Mg2SiO4, means rich silica SiO2. When pressure ranges between 2.5 and 5.5 GPa , it becomes a melting Alanstadtaat compatible .