Chapter Review:
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When any object or material transforms its colour, size and taste etc that is known as changes. Ex :- curd from milk, chapatti from Flour, chair from wood.
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There are two kinds of changes. (i) Physical changes (ii) Chemical changes.
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A change in which a substance undergoes a change in its physical properties is called a physical change.
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A change in which one or more new substances are formed is called a chemical change.
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This process of depositing a layer of zinc
on iron is called galvanisation. -
Large crystals of pure substances can be formed from their solutions. The process is called crystallisation.
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Oxygen and water (or water vapour) is essential for rusting.