This ppt prepared by Student-Teacher from Thiagarajar College of Preceptors-Madurai for Demo Class.

1. B.Ed.,PRACTICALEXAMINATION
(2019–2021)
LEVEL-ii

2. PURIFICATIONOFORGANICCOMPOUNDS

3. Contents
✓ Need for purification
✓ Methods for purification
✓ Purification of liquids
✓ Purification of solids

4. Need for purification
✓ To study the structure, Physical,
Chemical and Biological properties of
organic compounds they must be pure
in state.
✓ There are several methods by which
organic compounds can be purified.
✓ The method employed for purification
depend upon the nature of impurity
and nature or organic compound .

5. Techniques for separation and purification of organic compounds

6. sublimation
✓ Substance when heated pass directly from
solid to vapor without melting. On cooling
vapours will give back solids. It is called
SUBLIMATION
✓ Example: Camphor, Naphthalene
✓ It is useful to separate volatile and non-
volatile substance.

7. CRYSTALLIZATION
Steps involved in crystallization process,
1. Selection of Solvent
2. Preparation of solution
3. Filtration of hot solution
4. Crystallization
5. Isolation

8. DIFFERENTIAL EXTRACTION
✓ The process of removing a substance from its
aqueous solution by shaking with a suitable
organic solvent is termed Extraction.
✓ Organic substance present as solution in water
can be recovered from the solution by means of
a separating funnel.
✓ Organic solvent immisible in water forms a
separate layer.
✓ By means of separating funnel, organic and
aqueous layer can be separated easily.

9. distillation

14. CHROMATOGRAPHY
✓It is based on the principle that the constituents are
adsorbed on an adsorbent in varying degrees.
✓The adsorbents used are generally silica gel or
alumina.
✓When a mobile phase moves over the fixed phase,
different constituents of the mixture get adsorbed at
various distances over the fixed phase.

15. Methods of chromatography
1. Column Chromatography
2. Thin layer chromatography
3. Paper chromatography
4. Gas-liquid chromatography
5. Ion-exchange chromatography

16. COLUMN CHROMATOGRAPHY