Crystallization in Separation of Substances – Class 6 Science Experiment
Chapter Name: Separation of Substances
Activity Name: Crystallization in Separation of Substances
Activity Description:

The experiment involves the process of crystallization to separate a dissolved substance from a solution. In this case, the objective is to separate salt from a saltwater solution.
Required Items:
- Saltwater solution (prepared by dissolving salt in water)
- Beaker
- Glass rod
- Heat source (e.g., Bunsen burner or hot plate)
- Dish or evaporating dish
Step by Step Procedure:
- Take a saltwater solution in a beaker.
- Heat the beaker gently using a Bunsen burner or a hot plate.
- Stir the solution with a glass rod while heating (Figure).
- Continue heating the solution until all the water in the beaker has evaporated. Be cautious not to overheat or burn the solution.
- As the water evaporates, salt crystals will start forming in the dish.
- Once all the water has evaporated, you will find salt crystals and powder remaining in the dish.
Experiment Observations:
After the water evaporates, you will observe the formation of salt crystals in the dish. These crystals may vary in size and shape, but they will have a crystalline structure.
Precautions:
- Ensure proper ventilation in the area to avoid inhaling any fumes or vapors during the heating process.
- Use caution while heating the beaker to avoid any accidents or burns.
- Do not overheat the solution as it may lead to the decomposition of the salt or other undesired reactions.
- Handle the glass rod carefully to avoid breakage or injury.
- Dispose of the remaining solution and salt crystals properly.
Lesson Learnt from Experiment:
The experiment demonstrates the process of crystallization, which is a technique used to separate dissolved substances from a solution based on their different solubilities. In this case, heating the saltwater solution caused the water to evaporate, leaving behind salt crystals.
This process can be used to obtain pure substances from mixtures and is widely used in various industries and scientific research.