MAHARASHTRA Class 10: Chemical Reactions Videos | Chemical Reactions - Exam Decoded

Breaking of glass is an irreversible physical change. 

Breaking of glass is not a chemical change as there is no change in its molecular arrangement and properties; hence, it is only a physical change and not a chemical change. 

Absorption of heat and change in colour does not occur when we add zinc to dilute HCl. 

Respiration is an exothermic reaction; hence, we feel warm on covering our mouth with our hands.