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प्रश्न
The value of rate constant of a pseudo first order reaction ______.
विकल्प
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.
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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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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
For a reaction: 
Rate = k
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(iii) Write the unit of rate constant for this reaction.
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Which of the following statements is not correct about order of a reaction.
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 L–¹ |
Initial concentration of [B]/mol L–¹ |
Initial rate of formation of [C]/mol L–¹ s–¹ |
| 1. | 0.30 | 0.30 | 0.10 |
| 2. | 0.30 | 0.60 | 0.40 |
| 3. | 0.60 | 0.30 | 0.20 |
Consider the reaction A ⇌ B. The concentration of both the reactants and the products varies exponentially with time. Which of the following figures correctly describes the change in concentration of reactants and products with time?
Why can’t molecularity of any reaction be equal to zero?
Why molecularity is applicable only for elementary reactions and order is applicable for elementary as well as complex reactions?
The role of a catalyst is to change
In the presence of a catalyst, the heat evolved or absorbed during the reaction.
The number of molecules of the reactants taking part in a single step of the reaction is indicative of ______.
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