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The solvent utilized in single-solvent recrystallization must dissolve the crude reaction mixture only when it is heated to reflux. [3] The heated solution is then passively cooled, yielding a crystallized product absent of impurities. [3] The solid crystals are then collected utilizing a filtration apparatus and the filtrate is discarded. [4]
1,4-Naphthoquinone or para-naphthoquinone is a quinone derived from naphthalene. It forms volatile yellow triclinic crystals and has a sharp odor similar to benzoquinone. It is almost insoluble in cold water, slightly soluble in petroleum ether, and more soluble in polar organic solvents. In alkaline solutions it produces a reddish-brown color ...
Sodium naphthalene is an organic salt with the chemical formula Na + [C 10 H 8] −. In the research laboratory, it is used as a reductant in the synthesis of organic, organometallic, and inorganic chemistry. It is usually generated in situ. When isolated, it invariably crystallizes as a solvate with ligands bound to Na +. [1]
If mixed solvents are used, target compound and impurities are first dissolved in small amount of solvent, and then addition of another solvent causes desired compound to precipitate. This can be considered a crude form of recrystallization performed without changes in temperature.
A naphthalene molecule can be viewed as the fusion of a pair of benzene rings. (In organic chemistry, rings are fused if they share two or more atoms.) As such, naphthalene is classified as a benzenoid polycyclic aromatic hydrocarbon (PAH). [19] The eight carbon atoms that are not shared by the two rings carry one hydrogen atom each.
Solvent Density (g cm-3) Boiling point (°C) K b (°C⋅kg/mol) ... Naphthalene: 217.9 78.2 –6.80 Nitrobenzene: 210.8 5.24 5.7 –7.00 Phenol: 181.75 3.60 43.0 –7.27
The process is then repeated to increase the purity in a technique known as recrystallization. For biological molecules in which the solvent channels continue to be present to retain the three dimensional structure intact, microbatch [2] crystallization under oil and vapor diffusion [3] have been the common methods.
Acid–base extraction is a subclass of liquid–liquid extractions and involves the separation of chemical species from other acidic or basic compounds. [1] It is typically performed during the work-up step following a chemical synthesis to purify crude compounds [2] and results in the product being largely free of acidic or basic impurities.