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The activation energy for a first order ...

The activation energy for a first order reaction is 60 kJ `mol^(-1)` in the absence of a catalyst and 50 kJ `mol^(-1)` in the presence of a catalyst. How many times will the rate of reaction grow in the presence of the catalyst if the reaction proceeds at `27^@ `C ?

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To solve the problem, we will use the Arrhenius equation and the relationship between the rate constants of a reaction in the presence and absence of a catalyst. ### Step-by-step Solution: 1. **Identify Given Data**: - Activation energy without catalyst (Ea1) = 60 kJ/mol - Activation energy with catalyst (Ea2) = 50 kJ/mol - Temperature (T) = 27°C = 300 K (after converting to Kelvin) - Gas constant (R) = 8.314 J/(mol·K) 2. **Convert Activation Energies to Joules**: - Ea1 = 60 kJ/mol = 60,000 J/mol - Ea2 = 50 kJ/mol = 50,000 J/mol 3. **Apply the Arrhenius Equation**: The relationship between the rate constants (k1 for the reaction without catalyst and k2 for the reaction with catalyst) can be expressed as: \[ \log \left( \frac{k_2}{k_1} \right) = \frac{E_a1 - E_a2}{2.303 \cdot R \cdot T} \] 4. **Substitute Values into the Equation**: \[ \log \left( \frac{k_2}{k_1} \right) = \frac{60,000 - 50,000}{2.303 \cdot 8.314 \cdot 300} \] 5. **Calculate the Numerator**: \[ 60,000 - 50,000 = 10,000 \text{ J/mol} \] 6. **Calculate the Denominator**: \[ 2.303 \cdot 8.314 \cdot 300 \approx 5737.74 \] 7. **Calculate the Logarithm**: \[ \log \left( \frac{k_2}{k_1} \right) = \frac{10,000}{5737.74} \approx 1.743 \] 8. **Find the Antilog**: To find the ratio of the rate constants: \[ \frac{k_2}{k_1} = 10^{1.743} \approx 55.06 \] 9. **Conclusion**: The rate of reaction will grow approximately 55.06 times in the presence of the catalyst.

To solve the problem, we will use the Arrhenius equation and the relationship between the rate constants of a reaction in the presence and absence of a catalyst. ### Step-by-step Solution: 1. **Identify Given Data**: - Activation energy without catalyst (Ea1) = 60 kJ/mol - Activation energy with catalyst (Ea2) = 50 kJ/mol - Temperature (T) = 27°C = 300 K (after converting to Kelvin) ...
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