A simple experimental video on Crystallization process for Grade 9 NCERT Science, Chemistry. Lesson - The Solid State. It tells about What is Crystallization: Definition, Process, and Technique.

1. PROCESS OF CRYSTALLISATION

2. What is Crystallisation??
• Crystallisation is a process that separates a pure solid in
the form of its crystals from a solution.
• It is used to purify solids.

3. HOW CAN WE OBTAIN PURE COPPER SULPHATE
FROM AN IMPURE SAMPLE??

4. Step 1
• Take some (approximately 5g) of impure sample of copper
sulphate in a china dish

5. Step 2
• Dissolve it in minimum amount of water.

6. Step 3
• Filter the impurities out

7. Step 4
• Evaporate water from the copper
sulphate solution so as to get a
saturated solution.

8. Step 5
• Cover the solution with
a filter paper and leave it
undisturbed at room
temperature to cool slowly
for a day

9. Step 6
• You will obtain the crystals of copper sulphate in the
china dish

10. This process is called
Crystallisation

11. Observation 1
What do you observe in the china dish?
The saturated solution when left undisturbed converts
to pure crystals of the substance. Thus, one observes
crystals of pure substance in the china dish.

12. Observation 2
Do the crystals look alike?
No, when formation of crystals take place in a china
dish, we observe that all crystals of different
compounds looks different. Some are needle shaped,
cube shaped, hair shaped.

13. Observation 3
How will you separate the crystals from the liquid in
china dish?
We can separate the crystals from the liquid in the china
dish by filtration. The water will be separated out and
crystals will remain on filter paper.

14. Presentation by
R. Pranavaraj