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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.
In chemistry, an ionic crystal is a crystalline form of an ionic compound. They are solids consisting of ions bound together by their electrostatic attraction into a regular lattice . Examples of such crystals are the alkali halides , including potassium fluoride (KF), potassium chloride (KCl), potassium bromide (KBr), potassium iodide (KI ...
In chemistry, fractional crystallization is a stage-wise separation technique that relies on the liquid–solid phase change. This technique fractionates via differences in crystallization temperature and enables the purification of multi-component mixtures, as long as none of the constituents can act as solvents to the others.
Crystallization affects optical, mechanical, thermal and chemical properties of the polymer. The degree of crystallinity is estimated by different analytical methods and it typically ranges between 10 and 80%, with crystallized polymers often called "semi-crystalline". The properties of semi-crystalline polymers are determined not only by the ...
For example, FeSO 4 is named iron(2+) sulfate (with the 2+ charge on the Fe 2+ ions balancing the 2− charge on the sulfate ion), whereas Fe 2 (SO 4) 3 is named iron(3+) sulfate (because the two iron ions in each formula unit each have a charge of 3+, to balance the 2− on each of the three sulfate ions). [108]
In some cases, the degree of hydration can be critical to the resulting chemical properties. For example, anhydrous RhCl 3 is not soluble in water and is relatively useless in organometallic chemistry whereas RhCl 3 ·3H 2 O is versatile. Similarly, hydrated AlCl 3 is a poor Lewis acid and thus inactive as a catalyst for Friedel-Crafts reactions
A colloidal crystal is an ordered array of colloidal particles and fine grained materials analogous to a standard crystal whose repeating subunits are atoms or molecules. [1] A natural example of this phenomenon can be found in the gem opal, where spheres of silica assume a close-packed locally periodic structure under moderate compression.
Small-molecule and macromolecular crystallography differ in the range of possible techniques used to produce diffraction-quality crystals. Small molecules generally have few degrees of conformational freedom, and may be crystallized by a wide range of methods, such as chemical vapor deposition and recrystallization. By contrast, macromolecules ...