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Hess's law of constant heat summation is a direct consequence of:
ABoth the first and second laws together
BEnergy being a path function
CThe system being adiabatic
DEnthalpy being a state function
Answer & Solution
Correct answer: D. Enthalpy being a state function
Hess's law states that the enthalpy change for a reaction depends only on the initial and final states, not on the route taken. This is exactly the statement that enthalpy is a state function. It lets us add and subtract thermochemical equations to obtain the enthalpy of reactions that are difficult to measure directly.
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