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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]
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.
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]
Recrystallization [5] [6] is a process used to purify chemical compounds. A mixture of the impure compound and solvent is heated until the compound has dissolved. If there is some solid impurity remaining it is removed by filtration. When the temperature of the solution is subsequently lowered it briefly becomes supersaturated and then the ...
The hot mixture is then filtered to remove any insoluble impurities. The filtrate is allowed to slowly cool. Crystals that form are then filtered and washed with a solvent in which they are not soluble, but is miscible with the mother liquor. The process is then repeated to increase the purity in a technique known as recrystallization.
This page contains tables of azeotrope data for various binary and ternary mixtures of solvents. The data include the composition of a mixture by weight (in binary azeotropes, when only one fraction is given, it is the fraction of the second component), the boiling point (b.p.) of a component, the boiling point of a mixture, and the specific gravity of the mixture.
Naphthalene is a solid that sublimes gradually at standard temperature and pressure, [9] at a high rate, with the critical sublimation point at around 80 °C (176 °F). [10] At low temperature, its vapour pressure is high enough, 1 mmHg at 53 °C, [11] to make the solid form of naphthalene evaporate into gas. On cool surfaces, the naphthalene ...
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.