Which of the following is the best definition of Hess' Law?

A. Since enthalpy is a state function, it will be different if a reaction takes place in one step or a series of steps.
B. Heat is always released by the decomposition of 1 mole of a compound into its constitute elements.
C. Heat evolved in a given process can be expressed as the sum of the heats of several processes that, when added, yield the process of interest.
D. The enthalpy of a process is the difference between the enthalpy of the products and the enthalpy of the reactants.
E. At constant pressure the enthalpy change of a reaction is equal to the heat change of a reaction.
I think that the answer to this is D because to find the change in heat it is the final - initial.

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  1. Well, I think it's B.

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  2. Take a look at answer C and evaluate it.

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