Question

NCERT CLASS IX - Science Textbook
Chapter 2 - Is Matter Around Us Pure

Classify the following as chemical or physical changes:

• Cutting of trees
• Melting of butter in a pan
• Rusting of almirah
• Boiling of water to form steam
• Passing of electric current through water, and water breaking down into hydrogen and oxygen gas
• Dissolving common salt in water
• Making a fruit salad with raw fruits
• Burning of paper and wood

Answer 1

Cutting of trees is a physical change.
Melting of butter in a pan is a physical change.
Rusting of almirah is a chemical change.
Boiling of water to form steam is a physical change.
Passing of electric current through water, and water breaking down into oxygen and hydrogen gas is a chemical change.
Dissolving common salt in water is a physical change.
Making a fruit salad with raw fruits is a physical change.
Burning of paper and wood is a chemical change.

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Answer 2

1. Cutting of trees: Physical change.

2. Melting of butter in a pan: Physical change.

3. Rusting of almirah: chemical change.

4. Boiling of water to form steam: physical change.

5. Passing of electric current, through water and the water breaking down into hydrogen and oxygen gases: chemical change.

6. Dissolving common salt in water: physical change.

7. Making a fruit salad with raw fruits: physical change.

8. Burning of paper and wood: chemical change.