Concept explainers
Interpretation:
The presence of two separate layers, when aqueous sodium bicarbonate is added to an organic reaction mixture, is to be explained on the basis of solubility and polarity. The chemical species present in both aqueous and organic layers after reaction with sodium bicarbonate is to be listed. The reason to repeat sodium bicarbonate extraction thrice is to be mentioned.
Concept introduction:
According to acid–base chemistry, in a liquid/liquid extraction containing two immiscible liquids, the more polar compound dissolves in the aqueous layer, whereas the organic compound dissolves in the non-polar phase. The distribution coefficient gives the ratio of the concentration of the solute in a mixture of two immiscible solvents at equilibrium.
An organic compound will dissolve better in the organic layer than in most aqueous solutions, unless it has been converted to an ionic species, which makes it more water-soluble.
Sodium bicarbonate is used for the extraction in order to neutralize or remove acidic compounds.
A separating funnel is used to separate the mixture components between two liquids that are immiscible.
One phase is the aqueous and the other one is organic solvent.
This separation depends on the densities of the liquids.
The separating funnel runs on the concept of “like dissolve like” with different solutes being preferentially soluble in certain solvent.
When separating funnel is shaken, the two solvents mix and share a large surface area, which allows each solute to migrate to the solvent in which it is more soluble.
Le Chateliers principle is used to explain the change in pressure, temperature or concentration of the equilibrium shifts into the direction in which effect change from the system.
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Organic Chemistry
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