Which of the following statements about a catalyst is true? O Catalysts increase the rate of the reaction. O Catalysts increase the activation energy of a reaction. O Catalysts decrease the rate of the reaction. O Catalysts cause a system at equilibrium to shift towards the reactants. O Catalysts cause a system at equilibrium to shift towards the products.

Which of the following statements about a catalyst is true? O Catalysts increase the rate of the reaction. O Catalysts increase the activation energy of a reaction. O Catalysts decrease the rate of the reaction. O Catalysts cause a system at equilibrium to shift towards the reactants. O Catalysts cause a system at equilibrium to shift towards the products.

Chemistry for Engineering Students

4th Edition

ISBN:9781337398909

Author:Lawrence S. Brown, Tom Holme

Publisher:Lawrence S. Brown, Tom Holme

Chapter11: Chemical Kinetics

Section: Chapter Questions

Problem 11.96PAE: The following statements relate to the reaction for the formation of HI: H2(g) + I2(g) -* 2 HI(g)...

See similar textbooks

Similar questions

For a certain reaction, Ea is 135 kJ and H=45 kJ. In the presence of a catalyst, the activation energy is 39% of that for the uncatalyzed reaction. Draw a diagram similar to Figure 11.14 but instead of showing two activated complexes (two humps) show only one activated complex (i.e., only one hump) for the reaction. What is the activation energy of the uncatalyzed reverse reaction?
Can a reaction mechanism ever be proven correct? Can it be proven incorrect?
Hydrogen iodide, HI, decomposes in the gas phase to produce hydrogen, H2, and iodine, I2. The value of the rate constant, k, fur the reaction was measured at several different temperatures and the data are shown here: Temperature (K) k (M -1 5-1) 555 6.23107 575 2.42106 645 1.44104 700 2.01103 What is the value of the activation energy (in kJ/mol) for this reaction?
Experimental data are listed here for the reaction B: Time (s) IB] (mol/L) 0.00 0.000 10.0 0.326 20.0 0.572 30.0 0.750 40.0 0.890 Prepare a graph from these data, connect the points with a smooth line, and calculate the rate of change of [B] for each 10-s interval from 0.0 to 40.0 s. Does the rate of change decrease from one time interval to the next? Suggest a reason for this result. How is the rate of change of [AJ related to the rate of change of [B] in each time interval? Calculate the rate of change of [AJ for the time interval from 10.0 to 20.0 s. What is the instantaneous rate, A[B]/Ar, when [BI = 0.750 mol/L?
In the PhET Reactions under Options. (a) Leave the Initial Temperature at the default setting. Observe the reaction. Is the rate of reaction fast or slow? (b) Click Pause" and then Reset All, and then enter 15 molecules of A and 10 molecules of BC once again. Select Show Bonds" under Options. This time, increase the initial temperature until, on the graph, the total average energy line is completely above the potential energy curve. Describe what happens to the reaction.
The reaction NO(g) + O,(g) — NO,(g) + 0(g) plays a role in the formation of nitrogen dioxide in automobile engines. Suppose that a series of experiments measured the rate of this reaction at 500 K and produced the following data; [NO] (mol L ’) [OJ (mol L 1) Rate = -A[NO]/Af (mol L_1 s-1) 0.002 0.005 8.0 X 10"'7 0.002 0.010 1.6 X 10-'6 0.006 0.005 2.4 X IO-'6 Derive a rate law for the reaction and determine the value of the rate constant.
Use the data provided in a graphical method to determine the order and rate constant of the following reaction: 2PQ+W Time (s) 9.0 13.0 18.0 22.0 25.0 [P] (M) 1.077103 1.068103 1.055103 1.046103 1.039103
Experiments during a recent summer on a number of fireflies (small beetles, Lampyridaes photinus) showed that the average interval between flashes of individual insects was 16.3 s at 21.0C and 13.0 sat 27.8C. a. What is the apparent activation energy of the reaction that controls the flashing? b. What would be the average interval between flashes of an individual firefly at 30.0C? c. Compare the observed intervals and the one you calculated in part b to the rule of thumb that the Celsius temperature is 54 minus twice the interval between flashes.
Experimental data are listed here for the reaction A 2 B. (a) Prepare a graph from these data; connect the points with a smooth line; and calculate the rate of change of [B] for each 10-second interval from 0.0 to 40.0 seconds. Does the rate of change decrease from one time interval to the next? Suggest a reason for this result. (b) How is the rate of change of [A] related to the rate of change of [B] in each time interval? Calculate the rate of change of [A] for the time interval from 10.0 to 20.0 seconds.
Bacteria cause milk to go sour by generating lactic acid. Devise an experiment that could measure the activation energy for the production of lactic acid by bacteria in milk. Describe how your experiment will provide the information you need to determine this value. What assumptions must be made about this reaction?
. explain the difference between elementary reactions and multistep reactions.
The following statements relate to the reaction for the formation of HI: H2(g) + I2(g) -* 2 HI(g) Rate = it[HJ [I2J Determine which of the following statements are true. If a statement is false, indicate why it is incorrect. The reaction must occur in a single step. This is a second-order reaction overall. Raising the temperature will cause the value of k to decrease. Raising the temperature lowers the activation energy' for this reaction. If the concentrations of both reactants are doubled, the rate will double. Adding a catalyst in the reaction will cause the initial rate to increase.