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What is meant by galvanisation? Why is i...

What is meant by galvanisation? Why is it done?

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Galvanisation is a process wherein a thin layer of zinc metal gets deposited on iron objects. This is done to prevent rusting of iron by protecting it to come in contact with air and moisture. Zinc metal, being more reactive, reacts with air to form hard layer of zinc oxide, which prevents air from passing through it.
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LAKHMIR SINGH & MANJIT KAUR-PHYSICAL AND CHEMICAL CHANGES-EXERCISE
  1. Explain how, painting of an Iron gate prevents it from rusting.

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  2. Explain why, rusting of Iron objects is faster in coastal areas than i...

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  3. What is meant by galvanisation? Why is it done?

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  4. State two ways to prevent the rusting of iron.

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  5. What is stainless steel ? How is stainless steel made ? State an impor...

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  6. State three differences between a physical change and a chemical chang...

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  7. Write a word equation to represent the process of rusting of iron. Als...

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  8. Explain why, explosion of a firework (such as cracker) is said to be a...

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  9. Explain why, melting of ice to form water is said to be a physical cha...

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  10. What is meant by crystallisation ? State its one use.

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  11. Describe how, crystals of copper sulphate are prepared.

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  12. Give example of a chemical change which occurs by the action of heat.

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  13. Give example of a physical change which occurs by the action of heat.

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  14. What is a (a) physical change, and (b) chemical change ? Give two exam...

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  15. What is meant by the rusting of iron ? State two conditions necessary ...

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  16. What happens when an iron nail is kept immersed in copper sulphate sol...

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  17. What happens when baking soda is added to vinegar ? Write a word equat...

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  18. What happens when carbon dioxide gas is passed through lime water ? Wr...

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  19. When baking soda is mixed with lemon juice, bubbles are formed with th...

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  20. When a candle burns, both physical and chemical changes take place. Id...

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