During the recrystallization of a solid, the sample is dissolved in hot solvent then filtered while hot. The filtrate is allowed
to cool and the mixture is filtered a second time. What effect will result if the filtrate solution is cooled too rapidly? Small impure crystals will form. Small pure crystals will form. The maximum amount of the compound as a purified solid will be obtained. Large impure crystals will form.
<em>If the filtrate solution is cooled too rapidly, Small pure crystals will form.</em>
Explanation:
The crystals form by two processes, nucleation and particle growth. Thus the size of the crystals is determined by the predominance between one or the other. In order to obtain the lower number of nucleus and the larger crystals it is necessary to cool the solution slowly. If the solution is cooled too rapidly there is no time to the particles growth and the result will be small crystals. But also, a fast cooling avoid the impurities in the crystals.
. A closed system allows only energy transfer but no transfer of mass. Example: a cup of coffee with a lid on it, or a simple water bottle. ... In reality, a perfectly isolated system does not exist, for instance hot water in a thermos flask cannot remain hot forever.
