Q3. For a reaction with an activation energy of 50 kJ/mol, what is the rate constant at 300 K if R = 8.314 J/(mol·K)? (2022)
Solution:
Using the Arrhenius equation, k = Ae^(-Ea/RT). Calculate k using the given values.
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Q4. What is the rate law expression for a reaction that is first order with respect to A and second order with respect to B? (2022)
Solution:
The rate law for a reaction is determined by the order with respect to each reactant. For a first order with respect to A and second order with respect to B, the rate law is Rate = k[A][B]^2.
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Q5. For a reaction with an activation energy of 50 kJ/mol, what will happen to the rate if the temperature is increased by 20°C? (2022)
Solution:
Increasing the temperature generally increases the rate of reaction significantly due to higher kinetic energy.
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Q6. In a reaction, if the concentration of reactant A is halved, and the rate constant remains the same, how does the rate change for a first-order reaction? (2021)
Solution:
For a first-order reaction, if [A] is halved, the rate also halves.
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Q7. If the concentration of a reactant is tripled in a second-order reaction, how does the rate change? (2023)
Solution:
For a second-order reaction, if concentration is tripled, the rate increases by 3² = 9 times.
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Q8. The Arrhenius equation relates which of the following? (2023)
Solution:
The Arrhenius equation relates the rate constant (k) to temperature (T) and activation energy (Ea).
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Q9. If the rate of a reaction is directly proportional to the concentration of one reactant raised to the power of 3, what is the order of the reaction? (2023)
Solution:
The order of the reaction is third because the rate is proportional to the concentration raised to the power of 3.
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Q10. The half-life of a first-order reaction is given by which of the following expressions? (2020)
Solution:
For a first-order reaction, the half-life is constant and is given by the formula t1/2 = 0.693/k.
