A seed crystal may be added if crystallization does not initiate on its own. Scratching the inside wall of the container with a glass rod also helps induce crystallization. Suction filter the crystals. Wash the crystals with a small amount of ice cold solvent to remove traces of impurities left from the solution. Dry the crystals to remove solvent.
Air drying is usually best.
Vacuum drying speeds this process. Oven drying can be used only if the compound is stable to high temperatures and does not melt at the temperature of drying. Binary Solvents Binary solvents can be used when the compound is too soluble in one solvent but insoluble in another. An example would be ethyl acetate-hexane. They will be less soluble or insoluble in the nonpolar solvent hexane.