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Piperidine is used as a solvent and as a base. The same is true for certain derivatives: N-formylpiperidine is a polar aprotic solvent with better hydrocarbon solubility than other amide solvents, and 2,2,6,6-tetramethylpiperidine is a highly sterically hindered base, useful because of its low nucleophilicity and high solubility in organic ...
The tables below provides information on the variation of solubility of different substances (mostly inorganic compounds) in water with temperature, at one atmosphere pressure. Units of solubility are given in grams of substance per 100 millilitres of water (g/100 ml), unless shown otherwise. The substances are listed in alphabetical order.
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
Due to its poor solubility in water, piperine is typically extracted from black pepper by using organic solvents like dichloromethane. [5] The amount of piperine varies from 1–2% in long pepper, to 5–10% in commercial white and black peppers.
Hansen solubility parameters were developed by Charles M. Hansen in his Ph.D thesis in 1967 [1] [2] as a way of predicting if one material will dissolve in another and form a solution. [3] They are based on the idea that like dissolves like where one molecule is defined as being 'like' another if it bonds to itself in a similar way.
The optical absorption spectrum of pyridine in hexane consists of bands at the wavelengths of 195, 251, and 270 nm. With respective extinction coefficients ( ε ) of 7500, 2000, and 450 L·mol −1 ·cm −1 , these bands are assigned to π → π*, π → π*, and n → π* transitions.
Hindered amine light stabilizers (HALS) are chemical compounds containing an amine functional group that are used as stabilizers in plastics and polymers. [1] These compounds are typically derivatives of tetramethylpiperidine and are primarily used to protect the polymers from the effects of photo-oxidation; as opposed to other forms of polymer degradation such as ozonolysis.
The Hildebrand solubility parameter is the square root of the cohesive energy density: =. The cohesive energy density is the amount of energy needed to completely remove a unit volume of molecules from their neighbours to infinite separation (an ideal gas).