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www.GOALias.blogspot.comYou have learnt about physical andchemical changes. Try to identifychanges that you observe around youas physical or chemical changes.KeywordsChemical changeChemical reactionCrystallisationGalvanisationPhysical changeRustingWhat you have learnt• Changes can be of two types, physical and chemical.• Physical changes are changes in the physical properties of substances.No new substances are formed in these changes. These changes maybe reversible.• In chemical changes new substances are produced.• Some substances can be obtained in pure state from their solutions bycrystallisation.Exercises1. Classify the changes involved in the following processes as physical orchemical changes:(a) Photosynthesis(b) Dissolving sugar in water(c) Burning of coal(d) Melting of wax(e) Beating aluminium to make aluminium foil(f ) Digestion of food2. State whether the following statements are true or false. In case astatement is false, write the corrected statement in your notebook.(a) Cutting a log of wood into pieces is a chemical change. (True/False)(b) Formation of manure from leaves is a physical change. (True/False)PHYSICALAND CHEMICALCHANGES6565