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Class 9
Science
Is Matter Around Us Pure
classify the following as chemical or physical cha...

Question:
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 the water breaking down into hydrogen and oxygen gases,
• dissolving common salt in water,
• making a fruit salad with raw fruits, and
• burning of paper and wood.

Answer:

Physical change: There is no change in the chemical nature of substance. Only state change. for example: ice - water - water vapour.

Chemical change: A substance reacts with another substance and makes a new substance. It is an irreversible reaction.

• Physical change
• Physical change
• Chemical change (hydrated iron oxide)
• Physical change
• Chemical change
• Physical change
• Physical change
• Physical change (Co₂, smoke, water vapour, ash)

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