Some chemical reactions absorb energy rather than release it. Which of these phenomena are caused by chemical reactions that absorb energy? If you're not sure, make a guess

A chemical reaction absorbs energy which means it is endothermic reaction.

The reaction is endothermic if the energy of products is more than the energy of reactants.

The energy of products is more means that the bond energy of products is more than the bond energy of reactants.

so breaking of bond needs energy which is greater than the energy released in making of new bonds.

Enthalpy of reaction = Bond energy of reactants - Bond energy of products.