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Recrystallization

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Sis290025:
a. The following solvent selection data were collected for impure solid (A):

Solvent-------------Solubility at room temp.-----Solubility when heated--------------------Crystals formed when cooled

Methanol------------Insoluble------------------------Insoluble------------------------------------------(-)
Ethyl acetate-------Insoluble-----------------------Soluble-------------------------------------------very few
Cyclohexane--------Insoluble------------------------Soluble-----------------------------------------many
Toluene--------------Insoluble------------------------Soluble-----------------------------------------very few

Based on these results, what solvent or mixture of solvents might one consider using to recrystalline solid A?

I would choose cyclohexane as a solvent since the solute dissolves in hot solvent and crystals appear when the solvent is cool.  ???


b. The following is for impure solid B.


Solvent---------Solubility at room temp.-----Solubility when heated----------------Crystals formed when cooled

Water------------------Soluble-------------------------------(-)------------------------------------------(-)
Ethanol-----------------Soluble------------------------------(-)-------------------------------------------(-)
Dichloromethane----Insoluble------------------------Insoluble----------------------------------------(-)
Petroleum ether-----Insoluble------------------------Soluble-----------------------------------------very few
Toulene-----------------Insoluble------------------------Soluble-----------------------------------------many

Based on these results, what solvent/mixture of solvents might one consider using to rescystallize B?
I would choose toulene as a solvent since the solute dissolves in hot solvent and crystals appear when the solvent is cool.  ???

Thank you.

mike:
What is the question? ???

Sis290025:
I just modified it. (I'm sorry! :-[)

mike:
Looks right to me.

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