If the activation energy of a reaction increases, what happens to the rate constant (k)?   A. the rate constant decreases B. the rate constant stays the same C. there isn't enough information to predict what happens to the rate constant D. the rate constant increases

9. An increase in temperature increases the reaction rate. What is the best reason to explain this effect? A. a greater fraction of the collisions have the correct orientation of molecules B. the activation energy of the reaction will increase C. the activation energy of the reaction will decrease D. more collisions will have enough energy to exceed the activation energy

Answer the following question using the reaction coordinate diagram shown below. 280 240+ 200 160 120 80 40 Time What is the activation energy for the forward reaction? A. -80 kJ B. 240 kJ C. 80 kJ D. 160 kJ Heat content (H) kilojoules

A catalyst reduces the activation barrier of a certain reaction to zero and simultaneously increases the reaction rate at 323 K by a factor of 1.29 x105. What is the activation energy for the uncatalyzed reaction? O A. 21.3 kJ/mol O B. 42.5 kJ/mol O C. 3.80 kJ/mol D. 28.1 kJ/mol O E. 31.6 kJ/mol

7. Reactions A and B were studied and found to produce the given energy diagrams. 150 150 Energy 100 (kJ/mol) 100 Energy (kJ/mol) 50 50 Reaction progress Reaction progress Reaction A Reaction B A third reaction, C was studied with a measured activation energy of 55 KJ/mol. Assume all reactions take place at the same temperature. Reaction A is slowest a. b. Reaction B is slowest c. Reaction C is slowest d. All reactions happen at the same rate.

The addition of a catalyst(s) is an extra step in the overall reaction. Which of the following provides a benefit towards the additional step?   a. promotes the formation of the product faster   b. raises the temperature of the reaction   c. lowers the activation energy   d. the first step will always be slower   e. slows the overall reaction to minimize byproducts

Which of the following will decrease the activation energy, Ea, of a reaction? O Increasing the reactant concentrations Removing the products as they form O Increasing the temperature O Adding a catalyst O Decreasing the pressure A Moving to another question will save this response. M esc 20 F3 F1 F2 F4 F5 @ #3 24 4 Q W R. A

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Which of the following changes would most likely increase the rate of a reaction?   a. increasing the size of the reactant particles   b. decreasing the reaction temperature   c. decreasing the concentration of a reactant   d. decreasing the activation energy for the reaction

Which statement is INCORRECT with regard to kinetics? A. Each 10o C rise in temperature approximately doubles the rate of a reaction. B. The rate is expressed as the change in concentration per the change in time. C. The rate of reaction is always expressed as a positive value. D. The presence of a catalyst decreases the rate of reaction by lowering the Ea of the reaction. E. The effect that changing the concentration of a reactent has on the rate of a reaction must be determined experimentally.