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NEETChemistryThermodynamics (C)

How is the reaction enthalpy change (∆ r H) calculated for a chemical reaction?

Options

  1. A∆ r H= (sum of enthalpies of reactants) - (sum of enthalpies of products)
  2. B∆ r H= (sum of enthalpies of products) + (sum of enthalpies of reactants)
  3. C∆ r H= (sum of enthalpies of reactants) + (sum of enthalpies of products)
  4. D∆ r H= (sum of enthalpies of reactants) x (sum of enthalpies of products)

Correct answer

A. ∆ r H= (sum of enthalpies of reactants) - (sum of enthalpies of products)

Step-by-step solution

The reaction enthalpy change (∆ r H) is calculated by subtracting the sum of the enthalpies of the products from the sum of the enthalpies of the reactants in a balanced chemical equation.

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