Purifying Compounds by Recrystallization
Group 6
Silao, Ma Grace Arrelyn
Uyanib, Mary
Vitor, Mary Mae
Vuelban, John Nicholson
Wasil, Kaye Shanili
2H1
Chem 212.2
Nova Anorico
November 11, 2021
, INTRODUCTION
1.1 Rationale of the Experiment
Recrystallization is a method of purifying substances. The purification process is built
on the concept that the solubility of most substances increases with temperature. This
explains that as the temperature rises, so does the amount of solute that can be dissolved in a
solvent. Recrystallization involves an impure substance that has been dissolved to produce a
highly concentrated solution at a high temperature. These will also destroy the impurities that
are present. Upon heating, the solution has cooled to produce a purer substance. The size of
the crystals influences the purity of the compound, having larger crystals to be purer than
smaller crystals. Polarity is the most important aspect in recrystallization. The solute should
be most soluble in hot solvents and least soluble in cold solvents. Solubility behavior must
first be examined in understanding the recrystallization process. This implies that compounds
with similar structural properties will be soluble in one another. Furthermore, it is important
to consider the appropriate solvent which can be obtained through trial and error, and based
on predictions and observations.
1.2 Objectives
The main objective of this experiment is to understand the process of purifying
compounds by recrystallization. The experiment also addresses the specific objectives:
1. To separate the impure sample in the minimum amount of an appropriate hot solvent.
2. To purify organic compounds which are solids at room temperature.