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Karnataka Board PUCPUC Science 2nd PUC Class 12

Mark the incorrect statements: (i) Catalyst provides an alternative pathway to reaction mechanism. (ii) Catalyst raises the activation energy. (iii) Catalyst lowers the activation

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Question

Mark the incorrect statements:

(i) Catalyst provides an alternative pathway to reaction mechanism.

(ii) Catalyst raises the activation energy.

(iii) Catalyst lowers the activation energy.

(iv) Catalyst alters enthalpy change of the reaction.

Short/Brief Note
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Solution

(ii) Catalyst raises the activation energy.

(iv) Catalyst alters enthalpy change of the reaction.

Explanation:

(i) As the catalyst is added to the reaction medium rate of reaction increases by decreasing activation energy of molecule. Hence, it follows an alternative pathway.

(ii) Catalyst does not change the enthapy change of reaction. Energy of ‘reactant and product remain same in both catalysed and uncatalysed reaction.

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Chapter 4: Chemical Kinetics - Exercises [Page 54]

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NCERT Exemplar Chemistry Exemplar [English] Class 12
Chapter 4 Chemical Kinetics
Exercises | Q II. 30. | Page 54

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