What is Hess's Law of Constant Heat Summation and what property of enthalpy does it reflect?
Answer and explanation
Correct answer: A. Total enthalpy change is independent of the pathway taken
- Step 1: Hess's Law states that Delta H for an overall process is the sum of Delta H values for the individual steps. Step 2. This holds because enthalpy H is a thermodynamic state function depending solely on initial and final states. Answer: Total enthalpy change is independent of the pathway taken. Why not the others: Path-dependent quantities like work (w) and heat (q) do not satisfy Hess's Law.
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