In exothermic reaction, heat is released while endothermic reaction is just opposite of that. In an exothermic reaction the energy that is absorbed in the breaking of bonds is less than the energy that is released in the making of the bond.
Doing calculations for the endothermic and endothermic reactions is a very complex process and it hardly finds an exact result. It is enthalpy change which is considered as an easy process to determine the energy of a chemical reaction and the equipment that is suitable for the purpose is bomb calorimeter. The formula for the enthalpy change is given below: Enthalpy change= energy that is used in the reactions while breaking of bonds- energy that is released in the bond making products.
So you can say that according to the definition the value of enthalpy change is negative.
Doing calculations for the endothermic and endothermic reactions is a very complex process and it hardly finds an exact result. It is enthalpy change which is considered as an easy process to determine the energy of a chemical reaction and the equipment that is suitable for the purpose is bomb calorimeter. The formula for the enthalpy change is given below: Enthalpy change= energy that is used in the reactions while breaking of bonds- energy that is released in the bond making products.
So you can say that according to the definition the value of enthalpy change is negative.