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MHT CET202617 April 2026Morning ShiftChemistryThermodynamics (C)Actual

Which of the following equations is used to obtain enthalpy change of a reaction?

Options

  1. AH = H_P - H_R
  2. BH = H_R - H_P
  3. CH = H_P + H_R
  4. DH = H_P H_R

Correct answer

A. H = H_P - H_R

Step-by-step solution

The enthalpy change of a reaction is defined as the difference between the sum of the enthalpies of the products and the sum of the enthalpies of the reactants. H = H_P - H_R where H_P is the sum of enthalpies of products and H_R is the sum of enthalpies of reactants. Answer: H = H_P - H_R

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