Hess's law is a simple application of:
Correct answer: B. Law of conservation of energy
- A. Law of mass action
- B. Law of conservation of energy
- C. Law of conservation of mass
- D. Dalton's law of partial pressure
Explanation
Hess's law is based on the principle of the conservation of energy. It states that the total enthalpy change of a chemical reaction is independent of the pathway taken to reach the final products. In other words, the enthalpy change for a reaction is the same whether it occurs directly or through multiple steps. This is because energy is conserved in chemical reactions, and the difference in enthalpy is solely dependent on the initial and final states of the reactants and products.
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About Thermochemistry and Energetics of Chemical Reactions
Thermochemistry measures energy changes in chemical reactions and distinguishes exothermic from endothermic processes. Work covers systems, surroundings and state functions, internal energy, the first law of thermodynamics, enthalpy and Hess's law, including the sign conventions used when heat enters or leaves a system.
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