Give an example of a chemical reaction for each of the following situations:
(a) A change in colour is observed.
(b) A gas is evolved.
(c) Sound is produced.

AcademicChemistryNCERTClass 7

(a) Reaction between copper sulphate and iron metal – blue solution of copper sulphate changes to green solution of ferrous sulphate.
(b) Reaction between Sodium hydrogen carbonate and acetic acid – carbon dioxide gas is evolved.
(c) Burning of crackers produces a loud sound.
Updated on 10-Oct-2022 13:21:38