I am reading through material for a recrystallization experiment, and I had a few things I wasn't sure about;

Question

- Why once filtered, should the recrystallization solution be allowed to cool slowly, undisturbed, rather than quickly?

and

-What makes a good solvent, i.e. what are the characteristics of a good solvent for recrystallization???

for the first ques, i think it that step should be done because it allows the crystals to form properly. ANy help appreciated.

Answer 1

You're on the right track. Crystals that can form slowly form more perfect crystals with fewer "contaminating" particles getting caught within the crystal lattice. Cooling slowly aids the more perfect crystal process.
For the solvent, you want one that will dissolve the solute at higher temperatures (below the solvents boiling point and below the melting point of the solute) but isn't too soluble at lower temperatures (so it will crystallize easily).

Answer 2

Thank you =)