Which of the following statements is not true for the rate constant, k?

 1 large value of k indicates fast reactions. 2 The value of k is independent of the concentration of reactants 3 The value of k is independent of the concentration of products 4 The value of the rate constant, k, as the name suggests is always constant for a particular reaction at all temperatures.

Subtopic:  Arrhenius Equation |
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 Assertion (A): For an endothermic reaction, the potential energy of the reactant is more than the potential energy of the product. Reason (R): Reactant molecules before converting to product form an activated complex that has lower energy than reactants as well as the products.

 1 Both (A) and (R) are true and (R) is the correct explanation of (A). 2 Both (A) and (R) are true but (R) is not the correct explanation of (A). 3 (A) is true but (R) is false. 4 Both (A) and (R) are false.

Subtopic:  Arrhenius Equation |
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The rate of a reaction is decreased by 3.555 times when the temperature was changed from 40°C to 30°C. The activation energy (in kJ ${\mathrm{mol}}^{-1}$) of the reaction is:
(Take R=8.314 J  In 3.555=1.268)

1. 100 kJ/mol
2. 120 kJ/mol
3. 95 kJ/mol
4. 108 kJ/mol

Subtopic:  Arrhenius Equation |
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The rate constant, the activation energy and the Arrhenius parameter of a chemical reaction at $$25^{\circ}C$$ are $$3\times10^{-4}~s^{-1},104.4~kJ~mol^{-1}$$ and $$6\times10^{14}~s^{-1}$$ respectively. The value of the rate constant as $$T\rightarrow\infty$$ is

1.  $$2\times10^{18}~s^{-1}$$
2.  $$6\times10^{14}~s^{-1}$$
3.  $$\infty$$
4.  $$3.6\times10^{30}~s^{-1}$$
Subtopic:  Arrhenius Equation |
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The rate constants of a reaction at 500K is 0.02s–1 . The values of Ea is 18.230 kJ. The value of A is-

1. 1.61
2. 1.41
3. 1.81
4. 1.21

Subtopic:  Arrhenius Equation |
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NEET 2025 - Target Batch
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To view explanation, please take trial in the course.
NEET 2025 - Target Batch