A solid aromatic product from a nitration was purified by recrystallisation. The crude solid was dissolved in the minimum volume of hot solvent, the hot solution was filtered, and the filtrate was left to cool to room temperature. The crystals formed were filtered off under reduced pressure and washed with a small volume of cold solvent.
Explain why the minimum volume of hot solvent is used to dissolve the crude solid.
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Explain why the solution is left to cool to room temperature before the crystals are filtered off.
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Explain why the crystals are washed with a small volume of cold solvent.
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Suggest why cold, rather than warm, solvent is used for this washing.
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