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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.
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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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