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At a certain temperature, the first orde...

At a certain temperature, the first order rate constant `k_(1)` is found to be smaller than the second order rate constant `k_(2)`. If `E_(a)(1)` of the first order reaction is greater than `E_(a)(2)` of the second order reaction, then as temperature is raised:

A

`k_(2)` will increase faster than `k_(1)`

B

`k_(1)` will increase faster than `k_(2)` but will always remain less than `k_(2)`

C

`k_(1)` will increase faster than `k_(2)` and become equal to `k_(2)`.

D

`k_(1)` will increase faster than `k_(2)` and become greater than `k_(2)`.

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The correct Answer is:
To solve the problem, we need to analyze the relationship between the rate constants of first-order and second-order reactions as temperature increases, given the activation energies. ### Step-by-Step Solution: 1. **Understanding Rate Constants**: - The rate constant \( k \) of a reaction is temperature-dependent and can be described by the Arrhenius equation: \[ k = A e^{-\frac{E_a}{RT}} \] where \( A \) is the pre-exponential factor, \( E_a \) is the activation energy, \( R \) is the universal gas constant, and \( T \) is the temperature in Kelvin. 2. **Given Information**: - At a certain temperature, \( k_1 < k_2 \) (the first-order rate constant is smaller than the second-order rate constant). - The activation energy for the first-order reaction \( E_{a1} \) is greater than that for the second-order reaction \( E_{a2} \) (i.e., \( E_{a1} > E_{a2} \)). 3. **Effect of Temperature on Rate Constants**: - As temperature increases, both \( k_1 \) and \( k_2 \) will increase due to the exponential factor in the Arrhenius equation. - However, because \( E_{a1} > E_{a2} \), the first-order reaction is less sensitive to temperature changes compared to the second-order reaction. 4. **Comparing the Rate Constants**: - Since \( k_2 \) is initially greater than \( k_1 \) and the second-order reaction is more temperature-dependent (due to lower activation energy), \( k_2 \) will increase at a faster rate than \( k_1 \) as temperature rises. - Therefore, even though both constants increase, \( k_2 \) will remain greater than \( k_1 \) as the temperature continues to increase. 5. **Conclusion**: - As temperature is raised, \( k_1 \) will increase, but \( k_2 \) will increase at a faster rate, maintaining the inequality \( k_2 > k_1 \). ### Final Answer: As temperature is raised, \( k_2 \) will increase faster than \( k_1 \), and \( k_2 \) will remain greater than \( k_1 \). ---

To solve the problem, we need to analyze the relationship between the rate constants of first-order and second-order reactions as temperature increases, given the activation energies. ### Step-by-Step Solution: 1. **Understanding Rate Constants**: - The rate constant \( k \) of a reaction is temperature-dependent and can be described by the Arrhenius equation: \[ k = A e^{-\frac{E_a}{RT}} ...
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