How would the following affect the percent recovery and melting point of your un

Question

How would the following affect the percent recovery and melting point of your unknowns?
a) too much recrystallization solvent was used.
b) the hot solution was not gravity-filtered before cooling.
c) the hot solution was gravity-filtered and immediately plunged into an ice bath.
d) the crystals (after suction filtration) were washed with hot solvent.
e) the crystals were not washed at all.
f)  the crystals were not allowed to fully dry during vacuum filtration

The boiling point of a liquid can likewise be affected by several factors. What effect would each of the following changes have upon a distillation?
a) lowering atmospheric pressure (as in a vacuum distillation)
b) the presence of significant dissolved impurities
c) the presence of water sufficient to form an azeotrope

Explanation / Answer

a) Too much recrystallization solvent was used. This will lead to the solute in dissolved state in solution.
b) The hot solution was not gravity-filtered before cooling.So that the crystalls are in impure form in the solution.
c) The hot solution was gravity-filtered and immediately plunged into an ice bath.This will lead to the imperfection crystall formation of the compound.
d) The crystals (after suction filtration) were washed with hot solvent.From this the substance dissolved in solvent in little amount.
e) The crystals were not washed at all.we will get solvent impurities along with the crystalls.
f) the crystals were not allowed to fully dry during vacuum filtration.It leads to over weight of the crystalls i.e., it contains solvent mass also.

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