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Karnataka Board PUCPUC Science 2nd PUC Class 12

Assertion: The enthalpy of reaction remains constant in the presence of a catalyst. Reason: A catalyst participating in the reaction, forms different activated complex and lowers down the activatio - Chemistry

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Question

Assertion: The enthalpy of reaction remains constant in the presence of a catalyst.

Reason: A catalyst participating in the reaction, forms different activated complex and lowers down the activation energy but the difference in energy of reactant and product remains the same.

Options

  • Both assertion and reason are correct and the reason is correct explanation of assertion.

  • Both assertion and reason are correct but reason does not explain assertion.

  • Assertion is correct but reason is incorrect.

  • Both assertion and reason are incorrect.

  • Assertion is incorrect but reason is correct.

MCQ
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Solution

Both assertion and reason are correct and the reason is correct explanation of assertion.

Explanation:

AH = Activation Energy of forward reaction – Activation Energy of reverse reaction.

Catalyst does not alter heat of reaction because it affects activation energy of forward and reverse reactions equally.

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Chapter 4: Chemical Kinetics - Exercises [Page 59]

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NCERT Exemplar Chemistry [English] Class 12
Chapter 4 Chemical Kinetics
Exercises | Q V. 59. | Page 59

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