Changes Around Us Physical and Chemical Class 7 Questions and Answers Science Chapter 5
Changes Around Us Physical and Chemical Class 7 Questions and Answers Science Chapter 5 Q.1.Classify the changes involved in the following processes as physical or chemical 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 food Ans. (a) Chemical change (b) Physical change (c) Chemical change (d) Physical change (e) Physical change (/) Chemical change Q.2.(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) (c)Iron pipes coated with zinc do not get rusted easily. (True/ False) (d)Iron and rust are the same substances. (True/ False) (e)Condensation of steam is not a chemical change. (True/ False) Ans. (a)False Correct statement: Cutting a log of wood into pieces is an irreversible physical change. (b)False Correct statement: Formation of manure from leaves is a chemical change. (c) True (d...