TOPIC : PHYSICAL AND CHEMICAL CHANGES
1. ANSWER THE FOLLOWING
1. Classify the following changes into physical and chemical changes
(i) Galvanization of Iron
(ii) Explosion of fire work
(iii) Decaying of organic matter
(iv) Breaking of glass
(v) Formation of clouds
2. Name the gas formed when vinegar is mixed with baking soda.
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3. Why is burning magnesium ribbon in air a chemical change?
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4. What kind of change is shown by the tearing of paper?
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5. Explain the following
(a) Lime water turns milky on passing carbon dioxide gas into it.
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(b) Bubbles are produced when acetic acid is added to a solution of sodium bicarbonate.
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6. A student took a solution of copper sulphate in a beaker and put a clean iron nail into it and left it for about one hour.
(a) What change do you expect?
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(b) What type of change is this?
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(c) Write a word equation for the above reaction.
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7. Write whether magnetisation of steel is a physical change or not? How is it different from magnetisation of Iron?
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Please click on below link to download CBSE Class 7 Science Physical And Chemical Change Worksheet Set C
