Hess's law is analogous to:
Correct answer: B. 1st law of thermodynamics
- A. Law of heat summation
- B. 1st law of thermodynamics
- C. Law of increasing entropy
- D. Law of heat exchange
Explanation
Hess's Law is a direct consequence of the First Law of Thermodynamics and the fact that enthalpy is a state function. It states that the total enthalpy change for a reaction is independent of the path taken, which reflects the principle of conservation of energy.
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About Hess's Law
Hess's law states that the enthalpy change of a reaction is independent of the route because enthalpy is a state function. Calculations involve reversing and adding thermochemical equations, using standard enthalpies of formation or combustion, and finding an unknown reaction enthalpy without confusing enthalpy change with reaction rate.
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