Why is benzoic acid is extracted into ether then extracted into an alkali solution prior to being precipitated with strong acid in its preparation with grignard reagent?
When you're attempting to extract benzoic acid from other organic compounds, it is necessary to change its pH by adding a layer of an basic compound such as 1M NaOH so that the benzoic acid then can be separated from the organic layer within a separatory funnel. When in NaOH, the benzoic acid loses a proton and thus becomes its conjugate base (the benzoate ion). The benzoate ion is charged and thus become miscible in the aqueous layer. To extract benzoic acid (ie get it to precipitate out of solution), a strong acid such as HCl must be added to solution. After the extraction, lower the pH of the solution, and recrystalize (use ice after the recrystalization to get benzoic acid crystals to crash out).
This is the preparation of Insoluble Salts.Insoluble Salts can be made by precipitation. This involves mixing a solution that contains its Positive ions with another solution that contains its Negative ions, For example , insoluble silver chloride is precipitated when solutions of silver nitrate and sodium chloride solutions are mixed together.
The cell walls of plants are made of a sugar polymer called cellulose. Frequently this cellulose is formed into fibers to strengthen the plant and if the plant is taken and these cellulose fibers extracted and washed, they then then be precipitated out of solution as a mat. When dry this mat is paper.
Sodium perchlorate in high concentrations will remove from solution the detergent sodium dodecyl sulphate and protein complexed with it. This and the failure of proteins to be precipitated by ethanol from solutions containing a high concentration of sodium perchlorate can be utilized as efficient, rapid and simple deproteinization procedures during the preparation of nucleic acids.
IMPORTANT ORE: ALLUVIAL GRAVEL MAC ARTHUR FORREST cyanide process crushing and concentration: the ore is crushed and then concentrated by n froth flotation process roasting : the concentrated ore is roasted in excess of air when the impurities are oxidised and escape as their volatile liquid treated with KCN: IT IS TRETED WITH dil kcn for 24 hrs the gold dissolve from it and form complex solution of potassium aurocyanide 4au + 8KCN + 2HO…
Biphenyl will be dissolved in ether along with your desired product after Grignard synthesis. If you add an aqueous sodium hydroxide (NaOH) solution to this it will react with your desired product but not the biphenyl and form two layers of solution. One layer will be biphenyl dissovled in ether the other will be NaX (where X is your desired product, just with the Na attached to an oxygen rather than a H) dissolved in…