How should the enthalpy of an intermediate step be manipulated when used to produce an overall chemical equation?

Heat is not a State function hence it depends upon intermediate steps. We use Hess's law to calculate the enthalpy of a chemical reaction. Multiply the enthalpy by 1 if the chemical equation is reversed. Multiply the enthalpy by –1 if the chemical equation is reversed. Add 2 to the enthalpy if the coefficients must be doubled. Add 2 to the enthalpy if the coefficients must be cut in half.

hurricanes form in warm water