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In dentistry, syneresis is the expulsion of water or other liquid molecules from dental impression materials (for instance, alginate) after an impression has been taken. Due to this process, the impression shrinks a little and therefore its size is no longer accurate.
The over extraction of groundwater is a human caused activity that causes these ground failures that create pore spaces where water once was occupying. The sudden sinking of the soils surface causes infrastructure damage and a higher risk of flood damage due to the displacement of the Earth's surface.
Although PEG is inherently denser than water, it occupies the upper layer. This is believed to be due to its solvent 'ordering' properties, which excludes excess water, creating a low density water environment. [6] The degree of polymerization of PEG also affects the phase separation and the partitioning of molecules during extraction ...
The strength of the bonds between the metal ion and water molecules in the primary solvation shell increases with the electrical charge, z, on the metal ion and decreases as its ionic radius, r, increases. Aqua ions are subject to hydrolysis. The logarithm of the first hydrolysis constant is proportional to z 2 /r for most aqua ions.
A chaotropic agent is a molecule in water solution that can disrupt the hydrogen bonding network between water molecules (i.e. exerts chaotropic activity).This has an effect on the stability of the native state of other molecules in the solution, mainly macromolecules (proteins, nucleic acids) by weakening the hydrophobic effect.
Water molecules stay close to each other , due to the collective action of hydrogen bonds between water molecules. These hydrogen bonds are constantly breaking, with new bonds being formed with different water molecules; but at any given time in a sample of liquid water, a large portion of the molecules are held together by such bonds. [61]
The self-ionization of water (also autoionization of water, autoprotolysis of water, autodissociation of water, or simply dissociation of water) is an ionization reaction in pure water or in an aqueous solution, in which a water molecule, H 2 O, deprotonates (loses the nucleus of one of its hydrogen atoms) to become a hydroxide ion, OH −.
Boiling tea leaves in water extracts the tannins, theobromine, and caffeine out of the leaves and into the water, as an example of a solid-liquid extraction. Decaffeination of tea and coffee is also an example of an extraction, where the caffeine molecules are removed from the tea leaves or coffee beans, often utilising supercritical fluid ...