Multiple Choice
By what factor is the rate of a reaction changed if an enzyme lowers the activation energy (Ea) by 7.0 kJ/mol at 37°C, according to the Arrhenius Equation?
15. Chemical Kinetics
Arrhenius Equation
Back15. Chemical Kinetics
Arrhenius Equation
- Multiple ChoiceThe activation energy of a first-order reaction is 83.5 kJ/mol. The rate constant is 3.54 x 10⁻⁵ s⁻¹ at 45 °C. What is the rate constant at 65 °C?
- Multiple Choice
A reaction with an activation energy Ea = 55.00 kJ/mol is run at temperature of 30ºC. Determine the temperature required to increase the rate constant 3 times.
- Multiple ChoiceA reaction is found to have an activation energy of 108 kJ/mol. If the rate constant for this reaction is 4.60 × 10⁻⁶ s⁻¹ at 275 K, what is the rate constant at 366 K according to the Arrhenius Equation?
- Multiple Choice
The rate constant of a reaction at 32°C is 0.060/s. If the frequency factor is 3.1 × 1015 s–1, what is the activation barrier?
- Multiple Choice
The following data shows the rate constant of a reaction measured at numerous temperatures. Use the Arrhenius plot to determine the frequency factor for the reaction.
- Open Question
The rate of a certain reaction was studied at various temperatures. The table shows temperature (𝑇) and rate constant (𝑘) data collected during the experiments. Plot the data to answer the questions. What is the value of the activation energy, 𝐸a, for this reaction?
- Multiple ChoiceA certain first-order reaction has a rate constant of 2.63 x 10^-2 s^-1 at 22.0°C. What is the value of the rate constant k at 75.0°C if the activation energy Ea is 76.9 kJ/mol?
- Multiple ChoiceA certain first-order reaction has a rate constant of 1.0 × 10⁻³ s⁻¹ at 25°C. If the rate constant triples when the temperature is increased to 35°C, what is the activation energy Ea (in kJ/mol) for this reaction?
- Multiple ChoiceA certain reaction has an activation energy of 70.0 kJ/mol and a frequency factor of A = 2.60 × 10^12 M⁻¹·s⁻¹. Using the Arrhenius equation, what is the rate constant, k, of this reaction at 30.0 °C?
- Multiple ChoiceA common rule of thumb in organic chemistry is that increasing the temperature of a reaction at room temperature by 10°C doubles the rate. Calculate the activation energy (Ea) for a reaction that follows this rule of thumb. Assume room temperature is 25°C.
- Multiple ChoiceA particular first-order reaction has a rate constant of 1.35 × 10^2 s⁻¹ at 25.0°C. What is the magnitude of the rate constant k at 95.0°C if the activation energy Ea is 55.5 kJ/mol?
- Multiple ChoiceA particular first-order reaction has a rate constant of 1.35 × 10² s⁻¹ at 25.0°C. Using the Arrhenius equation, what is the rate constant (k) at 95.0°C if the activation energy (Ea) is 55.5 kJ/mol?
- Multiple ChoiceA particular first-order reaction has a rate constant of 1.35 x 10^0 s^-1 at 25°C. What is the magnitude of the rate constant k at 75.0°C if the activation energy Ea is 55.3 kJ/mol?
- Multiple ChoiceUsing the Arrhenius Equation, calculate the activation energy (Ea) in kilojoules per mole for a reaction with rate constants of 0.000116 s⁻¹ at 25 °C and 0.305 s⁻¹ at 85 °C. Express your answer to three significant figures.