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If K(1)= Rate constant at temperature T(...

If `K_(1)=` Rate constant at temperature `T_(1)` and `k_(2)` rate constant at temperature `T_(2)` for a first order reaction, then which of the following relation is correct ?

A

`"log "(k_(1))/(k_(2))=(2.303 E_(a))/(R) ((T_(2)-T_(1))/(T_(1)T_(2)))`

B

`"log"(k_(2))/(k_(1))=(E_(a))/(2.303 R) ((T_(2)-T_(1))/(T_(1)T_(2)))`

C

`"log "(k_(2))/(k_(1))=(E_(a))/(2.303 R) ((T_(1) T_(2))/(T_(2)+T_(1)))`

D

`"log "(k_(1))/(k_(2))=(E_(a))/(2.303 R)((T_(1)T_(2))/(T_(2)-T_(1)))`

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To solve the problem regarding the relationship between the rate constants \( k_1 \) and \( k_2 \) at different temperatures \( T_1 \) and \( T_2 \) for a first-order reaction, we can use the Arrhenius equation. Here’s a step-by-step breakdown of the solution: ### Step 1: Write the Arrhenius Equation for \( k_1 \) The Arrhenius equation relates the rate constant \( k \) to the temperature \( T \) as follows: \[ k_1 = A e^{-\frac{E_a}{RT_1}} \] where: - \( k_1 \) = rate constant at temperature \( T_1 \) - \( A \) = Arrhenius constant (frequency factor) - \( E_a \) = activation energy - \( R \) = universal gas constant - \( T_1 \) = temperature in Kelvin ### Step 2: Take the Natural Logarithm of \( k_1 \) Taking the natural logarithm of both sides gives: \[ \ln k_1 = \ln A - \frac{E_a}{RT_1} \] ### Step 3: Write the Arrhenius Equation for \( k_2 \) Similarly, for the rate constant \( k_2 \) at temperature \( T_2 \): \[ k_2 = A e^{-\frac{E_a}{RT_2}} \] ### Step 4: Take the Natural Logarithm of \( k_2 \) Taking the natural logarithm of both sides gives: \[ \ln k_2 = \ln A - \frac{E_a}{RT_2} \] ### Step 5: Subtract the Two Equations Now, we subtract the equation for \( k_1 \) from the equation for \( k_2 \): \[ \ln k_2 - \ln k_1 = \left(\ln A - \frac{E_a}{RT_2}\right) - \left(\ln A - \frac{E_a}{RT_1}\right) \] This simplifies to: \[ \ln k_2 - \ln k_1 = -\frac{E_a}{RT_2} + \frac{E_a}{RT_1} \] \[ \ln \frac{k_2}{k_1} = \frac{E_a}{R} \left(\frac{1}{T_1} - \frac{1}{T_2}\right) \] ### Step 6: Convert to Logarithm Base 10 To convert from natural logarithm to common logarithm (base 10), we use the conversion factor: \[ \ln x = 2.303 \log_{10} x \] Thus, we have: \[ \ln \frac{k_2}{k_1} = 2.303 \log_{10} \frac{k_2}{k_1} \] Substituting this into our equation gives: \[ 2.303 \log_{10} \frac{k_2}{k_1} = \frac{E_a}{R} \left(\frac{1}{T_1} - \frac{1}{T_2}\right) \] ### Step 7: Rearranging the Equation Rearranging the equation yields: \[ \log_{10} \frac{k_2}{k_1} = \frac{E_a}{2.303 R} \left(\frac{1}{T_1} - \frac{1}{T_2}\right) \] ### Conclusion This relationship shows how the rate constants \( k_1 \) and \( k_2 \) are related to the temperatures \( T_1 \) and \( T_2 \) through the activation energy \( E_a \) and the gas constant \( R \).

To solve the problem regarding the relationship between the rate constants \( k_1 \) and \( k_2 \) at different temperatures \( T_1 \) and \( T_2 \) for a first-order reaction, we can use the Arrhenius equation. Here’s a step-by-step breakdown of the solution: ### Step 1: Write the Arrhenius Equation for \( k_1 \) The Arrhenius equation relates the rate constant \( k \) to the temperature \( T \) as follows: \[ k_1 = A e^{-\frac{E_a}{RT_1}} \] where: ...
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