मराठी
कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान 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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प्रश्न

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.

पर्याय

  • 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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उत्तर

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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पाठ 4: Chemical Kinetics - Exercises [पृष्ठ ५९]

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एनसीईआरटी एक्झांप्लर Chemistry [English] Class 12
पाठ 4 Chemical Kinetics
Exercises | Q V. 59. | पृष्ठ ५९

संबंधित प्रश्‍न

A → B is a first order reaction with rate 6.6 × 10-5m-s-1. When [A] is 0.6m, rate constant of the reaction is

  • 1.1 × 10-5s-1
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  • 9 × 10-5s-1
  • 9 × 10-4s-1

For a reaction : 

(i) Write the order and molecularity of this reaction.

(ii) Write the unit of k.


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A reaction is first order in A and second order in B. Write the differential rate equation.


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Pseudo first-order reaction


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Compounds ‘A’ and ‘B’ react according to the following chemical equation.
\[\ce{A(g) + 2B(g) -> 2C(g)}\]
Concentration of either ‘A’ or ‘B’ were changed keeping the concentrations of one of the reactants constant and rates were measured as a function of initial concentration. Following results were obtained. Choose the correct option for the rate equations for this reaction.

Experiment Initial
concentration
of [A]/mol L¹
Initial
concentration
of [B]/mol L¹
Initial rate of
formation of
[C]/mol L¹ s¹
1. 0.30 0.30 0.10
2. 0.30 0.60 0.40
3. 0.60 0.30 0.20

For which type of reactions, order and molecularity have the same value?


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(i) What is the order of the reaction?

(ii) What is the slope of the curve?

(iii) What are the units of rate constant?


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