Key Practicals Part 2

Question 1

What is thermal decomposition?

Answer 1

Thermal decomposition is a chemical reaction where a compound breaks down into simpler substances when heated.

Example: Decomposition of Calcium Carbonate

Question 2

How is calcium carbonate decomposed?

Answer 2

Place calcium carbonate (limestone) in a boiling tube and heat it strongly with a Bunsen burner.

Observations: Limewater turns cloudy, indicating carbon dioxide formation.

Question 3

What is the conclusion of heating calcium carbonate?

Answer 3

Calcium carbonate decomposes upon heating to form calcium oxide and carbon dioxide.

Reaction: CaCO₃ → heat → CaO + CO₂

Question 4

What is distillation?

Answer 4

Distillation is a method used to separate liquids with significantly different boiling points.

Example: Separation of Ethanol and Water

Question 5

What apparatus is used in distillation?

Answer 5

Distillation flask, thermometer, and condenser are used in the distillation process.

Question 6

How is ethanol separated from water using distillation?

Answer 6

Heat a mixture of ethanol and water in a distillation flask; ethanol boils first and condenses in the condenser.

Observations: Ethanol distills before water.