Crystallization Process and Techniques

The video tutorial explains the process of crystallization, a physical change used to obtain pure substances from impure ones. It provides a step-by-step guide to conducting an experiment to grow copper sulfate crystals. The experiment involves heating water, adding sulfuric acid and copper sulfate, and allowing the solution to cool and form crystals over 24 hours. The tutorial emphasizes that crystallization is a method for purification without forming new substances.

What is the process of obtaining crystals from a hot saturated solution called?

• Distillation

• Crystallization

• Filtration

• Evaporation

Why is crystallization considered a physical change?

• It changes the chemical composition.

• It is irreversible.

• It involves a change in physical state only.

• It creates new substances.

What is the purpose of adding dilute sulfuric acid in the experiment?

• To speed up the crystallization

• To cool the solution

• To dissolve impurities

• To purify the copper sulfate

At what point should you stop adding impure copper sulfate?

• When no more copper sulfate dissolves

• When the water evaporates

• When the solution turns blue

• When the solution starts boiling

What should be done after pouring the saturated copper sulfate solution into a glass?

• Cover it with a cardboard lid

• Stir it continuously

• Heat it further

• Add more sulfuric acid

How long should the setup be left undisturbed to form crystals?

• 12 hours

• 24 hours

• 48 hours

• 72 hours

What is the final step after obtaining the crystals?

• Reheat the solution

• Add more water

• Filter the solution

• Dry the crystals in warm air