why is diethyl ether not used as asolvent for recrystallisation?

Answer 1

The most obvious reason is because it evaporates so quickly. The cooling that takes place during evaporation causes water from the atmosphere to condense on it's surface. This would lead to "wet" crystals.

Also, upon filtering the purified organic crystals you would see "ice crystals" form on the filter paper as the diethyl ether evaporated.

A practical reason is because it is not one of the better solvents for most organic materials that one would wish to purify by recrystallization. Alcohols are better for polar materials and benzene, dichloromethane or a petroleum hydrocarbon are better for others.

In terms of student lab, the anesthetic effects of the ether must also be considered.

Answer 2

The boiling point of diethyl ether is only 35degC or 95degF, which is the temperature of a warm day. So it would be hard to control the concentration of solute in the ether while pouring it around and filtering a solution. Too, the procedure would probably use ice to chill the solution to get the crystals. Thus you'd have only a 35degC temperature difference between boiling solvent and 0degC.

Answer 3

First, diethyl ether is a polar solvent, not very polar, but a 2.8 on a scale of 0 (hexane) to 6 (acetic acid).It can be used with solvents such as hexane for crystallization as the polar component.

The reasons for ether not being used for crystallization can depend on who is making the statement under what circumstances. For students, the main problems are the volatility, safety concerns, and flammability (already mentioned). It also can also form inclusion crystals similar to hydrated compounds and you don't get very well formed or very pure crystals. However, it can be used in certain cases, especially for organic and organometallic compounds. Usually, there are better choices.

Answer 4

Matahari is right. Diethyl ether is non polar. For recrystallisation to occur the substance must dissolve in the solvent. If it is an ionic salt that you are recrystallising, then the salt is polar and will not dissolve in a non polar solvent. REMEMBER: like dissolves like

Answer 5

Well it depends on what your dissolving into it. The solvent has to dissolve a minimum amount of impure substance at low temperature and dissolve a large amount at higher temperatrue. I normally use EtOH for organic substances but remember like disolves like and the boiling point of the solvent must not be higher than the melting point of the solute and it cant react with the solution.

Answer 6

Usually polar solvents are used for recrystallization. Diethyl ether is not polar.

Answer 7

I haven't got a clue what trimyristin is but my guess would be that it is non-polar (since ether is the preferred solvent) and that the solubility's would be ether