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NEETChemistryThermodynamics (C)

According to Hess's Law, what is the relationship between the standard reaction enthalpy of a reaction that occurs in several steps and the standard enthalpies of the intermediate reactions?

Options

  1. AThe standard reaction enthalpy is always greater than the sum of the standard enthalpies of the intermediate r
  2. BThe standard reaction enthalpy is always equal to the sum of the standard enthalpies of the intermediate react
  3. CThe standard reaction enthalpy is always less than the sum of the standard enthalpies of the intermediate reac
  4. DThe standard reaction enthalpy has no relationship with the standard enthalpies of the intermediate reactions.

Correct answer

B. The standard reaction enthalpy is always equal to the sum of the standard enthalpies of the intermediate react

Step-by-step solution

According to Hess's Law, the standard reaction enthalpy of a reaction that occurs in several steps is equal to the sum of the standard enthalpies of the intermediate reactions into which the overall reaction may be divided at the same temperature.

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