The amount of energy in the bonds of the reactants plus any energy absorbed equals the amount of energy in the bonds of the products plus any energy

The amount of energy in the bonds of the reactants plus any energy absorbed equals the amount of energy in the bonds of the products plus any energy given off when the products are formed.

This statement explains and verifies the law of conservation of energy during the chemical reactions. This law states that energy can neither be created nor destroyed, but can change from one form to another.

You would be correct, boiling water does disinfect contamination.    the property of disinfecting means to kill  germs, bacteria and other pathogens or contamination  that might cause an infection or cause a person to become sickly. a couple methods of disinfecting are using soap, other cleaning supplies or by simply "boiling" the contaminate.  the reason why boiling water disinfects certain attributes is because some cells cannot survive the heat and pressure.