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MHT CET202620 April 2026Morning ShiftChemistryThermodynamics (C)Actual

Identify the law for the statement "Overall the enthalpy change for a reaction is equal to sum of enthalpy changes of individual steps in the reaction"

Options

  1. AFirst law of thermodynamics
  2. BHess's law
  3. CAvogadro's law
  4. DSecond law of thermodynamics

Correct answer

B. Hess's law

Step-by-step solution

Hess's law of constant heat summation states that the total enthalpy change for a chemical reaction is independent of the path by which the reaction occurs. If a reaction takes place in several steps, the overall enthalpy change is equal to the sum of the enthalpy changes of the individual steps. This is because enthalpy is a state function, meaning it depends only on the initial and final states of the system, not on the path taken. Answer: Hess's law

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