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Karnataka Board PUCPUC Science 2nd PUC Class 12

Which of the following statements is not correct about order of a reaction.

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Question

Which of the following statements is not correct about order of a reaction.

Options

  • The order of a reaction can be a fractional number.

  • Order of a reaction is experimentally determined quantity.

  • The order of a reaction is always equal to the sum of the stoichiometric coefficients of reactants in the balanced chemical equation for a reaction.

  • The order of a reaction is the sum of the powers of molar concentration of the reactants in the rate law expression.

MCQ
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Solution

The order of a reaction is always equal to the sum of the stoichiometric coefficients of reactants in the balanced chemical equation for a reaction.

Explanation:

In rate law expression, the order of reaction is equal to the sum of the power of concentration of the reactants.

\[\ce{xA + yB -> zC}\]

r = k(A)x (B)y

Order x + y

The order of the reactions can also be a fraction. In a balanced chemical equation, the order of reaction may or may not be equal to the total of the stoichiometric coefficient of the reactants.

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Chapter 4: Chemical Kinetics - Exercises [Page 49]

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NCERT Exemplar Chemistry Exemplar [English] Class 12
Chapter 4 Chemical Kinetics
Exercises | Q I. 9. | Page 49

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