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An example of this crystallization process is the production of Glauber's salt, a crystalline form of sodium sulfate. In the diagram, where equilibrium temperature is on the x-axis and equilibrium concentration (as mass percent of solute in saturated solution) in y-axis , it is clear that sulfate solubility quickly decreases below 32.5 °C.
Additional energy is released upon melting a semicrystalline polymer. This energy can be measured with differential scanning calorimetry and compared with that released upon melting of the standard sample of the same material with known crystallization degree. [6] [20] X-ray diffraction
The energy released/absorbed by phase transition from solid to liquid, or vice versa, the heat of fusion is generally much higher than the sensible heat. Ice, for example, requires 333.55 J/g to melt, but then water will rise one degree further with the addition of just 4.18 J/g.
Water of crystallization can generally be removed by heating a sample but the crystalline properties are often lost. Compared to inorganic salts, proteins crystallize with large amounts of water in the crystal lattice. A water content of 50% is not uncommon for proteins.
The concept of lattice energy was originally applied to the formation of compounds with structures like rocksalt and sphalerite where the ions occupy high-symmetry crystal lattice sites. In the case of NaCl, lattice energy is the energy change of the reaction Na + (g) + Cl − (g) → NaCl (s) which amounts to −786 kJ/mol. [2]
Examples can include Latent internal energy of vaporization (liquid to vapor), Latent internal energy of crystallization (liquid to solid) Latent internal energy of sublimation (solid to vapor). These values are usually expressed in units of energy per mole or per mass such as J/mol or BTU/lb. Often a negative sign will be used to represent ...
One example of Ostwald ripening is the re-crystallization of water within ice cream which gives old ice cream a gritty, crunchy texture. Larger ice crystals grow at the expense of smaller ones within the ice cream, creating a coarser texture. [15]
Time crystals: A state of matter where an object can have movement even at its lowest energy state. Hidden states of matter: Phases that are unattainable or do not exist in thermal equilibrium, but can be induced e.g. by photoexcitation. Microphase separation: Constituent units forming diverse phases while also keeping united.