मराठी
कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान 2nd PUC Class 12

The value of rate constant of a pseudo first order reaction ______.

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प्रश्न

The value of rate constant of a pseudo first order reaction ______.

पर्याय

  • depends on the concentration of reactants present in small amount.

  • depends on the concentration of reactants present in excess.

  • is independent of the concentration of reactants.

  • depends only on temperature.

MCQ
रिकाम्या जागा भरा
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उत्तर

The value of rate constant of a pseudo first order reaction depends on the concentration of reactants present in excess.

Explanation:

Let's start with what a pseudo-first-order response is.

Although the pseudo-first-order reaction looks to be an order, it belong to another order. it's a second-order reaction because it involves two reactants.

Let's have a look at a reaction.

\[\ce{CH3Br + OH -> CH3OH + Br}\]

So, the rate law for the reaction is 

Rate = \[\ce{k[OH][CH3Br]}\]

Rate = \[\ce{k[OH][CH3Br] = k(constant) [CH3Br] = K' [CH3Br]}\]

Only the concentration of \[\ce{CH3Br}\] will change during the reaction and the rate will be determined by the reaction's modifications.

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पाठ 4: Chemical Kinetics - Exercises [पृष्ठ ५२]

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एनसीईआरटी एक्झांप्लर Chemistry Exemplar [English] Class 12
पाठ 4 Chemical Kinetics
Exercises | Q I. 19. | पृष्ठ ५२

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

What is pseudo first order reaction? Give one· example of it.


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Rate = k

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(ii) Write the unit of k.


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