This document provides instructions for purifying an organic compound through recrystallization. It explains that recrystallization works by dissolving an impure sample in a hot solvent, then allowing the solution to cool slowly, causing the pure compound to crystallize out while impurities remain in solution. The procedure involves weighing the impure sample, dissolving it in a suitable heated solvent, cooling the solution in an ice bath to induce crystallization, filtering out the crystals, and allowing them to dry. The goal is to purify the organic compound sample through crystallization.

1. PRACTICAL ORGANIC
CHEMISTRY
Prepared By
Ms.Sayyed Mohsina

2. OBJECT
• To perform the recrystallization of a given impure organic
compound.

3. REQUIREMENTS
• Apparatus required
• Beaker ,conical flask, water bath ,reagent bottle, measuring
cylinder, pipette, glass rod, spachula , funnel etc
• Chemicals required
• Solvent and sample of organic compound

4. THEORY
• Crystallization is a process to purify solids.Crystallization may
be defined as the process in which a solid compound
precipitates from a saturated solution in the form of crystals.
Saturation is usually effected through cooling .
• Purification by recrystallization depends on the following facts:
1. Different solids have different solubilities in a given solvent.
2. Most solids are more soluble in hot than in cold solvents.

5. RECRYSTALLIZATION
• In recrystallization procedure,an impure or crude solid dissolve
in Hot solvent.
• As a hot saturated solution cools, the solute precipitated out.
• The pure product crystallizes out and the impurities remains in
the solvent or stay dissolved in it.

6. PROCEDURE
• Weigh about one gram of unknown impure organic compound.
• Dissolved the weighed sample in the small amount of selected solvent .
• The suitable solvent obtained by making a solubility test on pure unknown
compound so as to choose the suitable solvent.
• Heat the solution in water bath to completely dissolve the sample.
• When all the the solid is in the solution, remove from the water bath.
• Place the Beaker in an ice bath For crystallization process.
• Now filter the solution to isolate the crystals.
• Carefully remove the crystals from filter paper to watch glass and allow it
to dry.

7. RESULT
• Recrystallization of given impure organic compound was
performed.