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For a first order reaction A rarr P, the...

For a first order reaction `A rarr P`, the temperature `(T)` dependent rate constant `(k)` was found to follow the equation `log k = -2000(1//T) + 6.0`. The pre-exponential factor `A` and the activation energy `E_(a)`, respective, are

A

`1.0 xx 10^(6) s^(-1)` and `9.2 kJ mol^(-1)`

B

`6.0 s^(-1)` and `16.6 kJ mol^(-1)`

C

`1.0 xx 10^(6) s^(-1)` and `16.6 kJ mol^(-1)`

D

`1.0 xx 10^(6) s^(-1)` and `38.3 kJ mol^(-1)`

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To solve the problem, we need to extract the pre-exponential factor \( A \) and the activation energy \( E_a \) from the given equation for the temperature-dependent rate constant \( k \): \[ \log k = -2000 \left(\frac{1}{T}\right) + 6.0 \] ### Step 1: Identify the Arrhenius Equation The Arrhenius equation is given by: \[ k = A e^{-\frac{E_a}{RT}} \] Taking the logarithm of both sides gives: \[ \log k = \log A - \frac{E_a}{2.303RT} \] ### Step 2: Rearranging the Given Equation We can rearrange the given equation to match the form of the Arrhenius equation: \[ \log k = -2000 \left(\frac{1}{T}\right) + 6.0 \] This can be compared to: \[ \log k = \log A - \frac{E_a}{2.303R} \cdot \frac{1}{T} \] ### Step 3: Identify \( A \) From the comparison, we can see that: \[ \log A = 6.0 \] To find \( A \), we take the antilogarithm: \[ A = 10^{6.0} = 1 \times 10^6 \] ### Step 4: Identify \( E_a \) Now, we compare the coefficients of \( \frac{1}{T} \): \[ -\frac{E_a}{2.303R} = -2000 \] This simplifies to: \[ \frac{E_a}{2.303R} = 2000 \] Now, we can solve for \( E_a \): \[ E_a = 2000 \times 2.303 \times R \] Where \( R = 8.314 \, \text{J mol}^{-1} \text{K}^{-1} \). Plugging in the value of \( R \): \[ E_a = 2000 \times 2.303 \times 8.314 \] Calculating this gives: \[ E_a = 2000 \times 2.303 \times 8.314 \approx 38300 \, \text{J mol}^{-1} \] Converting to kilojoules: \[ E_a \approx 38.3 \, \text{kJ mol}^{-1} \] ### Final Answer Thus, the pre-exponential factor \( A \) and the activation energy \( E_a \) are: \[ A = 1 \times 10^6 \quad \text{and} \quad E_a = 38.3 \, \text{kJ mol}^{-1} \]

To solve the problem, we need to extract the pre-exponential factor \( A \) and the activation energy \( E_a \) from the given equation for the temperature-dependent rate constant \( k \): \[ \log k = -2000 \left(\frac{1}{T}\right) + 6.0 \] ### Step 1: Identify the Arrhenius Equation The Arrhenius equation is given by: ...
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