NCERT Q1 - Is Matter Around Us Pure?
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, burning of paper and wood.
Answer: Physical: cutting trees, melting butter, boiling water, dissolving salt, making salad. Chemical: rusting, electrolysis of water, burning.
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