Question

Explain in brief the involvement of energy in - physical & Chemical changes.

Answer 1

An endothermic reaction takes place when energy is absorbed from surroundings in the form of heat, and exothermic is when energy is released from the system into the surroundings. Both of them are mostly occured in physical and chemical changes

For example, when solid dry ice vaporizes (physical change), carbon dioxide molecules absorb energy. Meanwhile, when liquid water becomes ice energy is released. Remember that all chemical reactions involve a change in the bonds of the reactants. ... Chemical bonds have potential energy or "storedenergy

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