Hess's law is used to measure the enthalpy of a desired chemical reaction because: D. Intermediate equations with known enthalpies are added together.
Hess's Law is also known as Hess's law of constant heat summation (enthalpy) and it was named after a Swiss-born Russian chemist called Germain Hess.
Hess's Law states that the energy change (enthalpy) experienced in a desired chemical reaction is equal to the sum of the energy changes (enthalpies) in each chemical reactions that it is made up of or contains.
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