EVERYDAY SCIENCE

Detailed explanation-1: -All chemical reactions involve changes in energy. This may be a change in heat, electricity, light, or other forms of energy. Reactions that absorb energy are endothermic. Reactions that release energy are exothermic.

Detailed explanation-2: -A particular chemical reaction absorbs energy or releases energy depending on the number and types of bonds broken and formed during the reaction. In many chemical reactions, the energy absorbed and released is in the form of heat. A chemical reaction in which heat is released is called an exothermic reaction.

Detailed explanation-3: -Chemical reactions that release energy are called exothermic. In exothermic reactions, more energy is released when the bonds are formed in the products than is used to break the bonds in the reactants.

Detailed explanation-4: -(Endothermic change) Conversion of a liquid substance into a solid substance-Heat energy released(Exothermic change) Example: Melting of ice absorbs heat energy, and water while boiling absorbs heat energy.