Reaction Rates and Chemical Equilibrium Test Bank | Kinetics, Collision Theory, Le Chatelier's Principle

REACTION RATES AND CHEMICAL
EQUILIBRIUM
Student: ___________________________________________________________________________

1. Which of the following best describes the rates of chemical reaction?
A. most chemical reactions occur very slowly
B. most chemical reactions occur at moderate rates
C. most chemical reactions occur very rapidly
D. chemical reactions have a wide range of rates, from extremely fast to extremely slow



2. Which of the following is the study of the rates of chemical reactions?
A. kinetics
B. stoichiometry
C. thermodynamics
D. none of these



3. Which of the following units can used to describe the rate of a chemical reaction?
A. (moles·liter)/minute
B. (moles/L)/minute
C. 1/(moles·liter·minute)
D. none of these



4. For the reaction A + B ® 2 C, which of the following best describes how we can measure the
reaction rate?
A. The rate can be measured by measuring how fast A is consumed.
B. The rate can be measured by measuring how fast C is produced.
C. either of the above procedures can be used
D. neither of the above procedures can be used

,5. For the reaction A + B ® 2 C, which of the following statements is true?
A. B is consumed at the same rate that A is consumed
B. C is produced at the same rate A is consumed
C. both a. and b.
D. Neither a. nor b.



6. For the reaction A + B ® 2 C, which of the following statements is true?
A. B is consumed at the same rate that A is consumed
B. C is produced at twice the rate A is consumed
C. both a. and b.
D. Neither a. nor b.



7. For the reaction 2C ® A + B, 0.01 mole of A is formed during the first 15 seconds of the
reaction. Assuming that the rate of reaction remains constant for two minutes, which of the
following statements is true?
A. after 2 minutes 0.08 moles of B were produced
B. after 2 minutes 0.08 moles of C were consumed
C. both a. and b.
D. Neither a. nor b.



8. For the reaction 2C ® A + B, 0.01 mole of A is formed during the first 15 seconds of the
reaction. Assuming that the rate of reaction remains constant for two minutes, which of the
following statements is true?
A. after 2 minutes 0.08 moles of B were produced
B. after 2 minutes 0.16 moles of C were consumed
C. both a. and b.
D. Neither a. nor b.



9. Which of the following is true of the rates of most chemical reactions?
A. the initial rate is cannot be measured
B. the initial rate is faster than the rate later in time
C. the initial rate is the same as the rate later in time
D. the initial rate is slower than the rate later in time

,10. In the reaction 2HgO(s) ® 2Hg(l) + O2(g) we measure the evolution of gas to determine the rate of
reaction. At the beginning of the reaction (at 0 minutes), 0.020 L of O2 is present. After 15
minutes the volume of O2 is 0.35 L. What is the rate of reaction?
A. 0.022 L/min
B. 0.023 L/min
C. 0.23 L/min
D. 0.33 L/min



11. Which of the following is true of effective collisions?
A. the number of effective collisions decreases as the temperature is increased
B. the number of effective collisions determines the reaction rate
C. both a. and b.
D. Neither a. nor b.



12. Which of the following is true of effective collisions?
A. the number of effective collisions determines the reaction rate
B. the number of effective collisions increases as the temperature is increased
C. both a. and b.
D. Neither a. nor b.



13. Many molecular collisions do not result in chemical reaction. Why is this?
A. the colliding molecules are not the correct chemicals
B. the colliding molecules do not have sufficient energy
C. the colliding molecules do not have the correct orientations
D. all of the above



14. Why will increasing the temperature of a reaction speed up the reaction?
A. the activation energy for the reaction is lowered
B. the heat of reaction is increased
C. there are more effective collisions between molecules
D. none of these



15. For which of the following reactions is it important that the species collide with the correct
orientation?
A. 2 NO(g) + O2(g) ® 2 NO2(g)
B. HCl(g) + H2O(l) ® H3O+(aq) + Cl-(aq)
C. both of them
D. neither of them

, 16. For which of the following reactions is it important that the species collide with the correct
orientation?
A. HCl(g) + H2O(l) ® H2O+(aq) + Cl-(aq)
B. Ag+(aq) + Cl--(aq) ® AgCl(s)
C. both of them
D. neither of them



17. For which of the following reactions is it important that the species collide with the correct
orientation?
A. 2 H2 (g) + O2 (g) ® 2 H2O(l)
B. HCl(g) + H2O(l) ® H2O+(aq) + Cl-(aq)
C. both of them
D. neither of them



18. Which of the following is true?
A. decreasing the activation energy decreases the reaction rate
B. decreasing the activation energy increases the reaction rate
C. the activation energy of an exothermic reaction is negative
D. there is no relationship between activation energy and reaction rate



19. Which of the following is true?
A. decreasing the activation increases the reaction rate
B. the activation energy for an exothermic reaction is negative
C. both a. and b.
D. Neither a. nor b.



20. In an energy diagram for a chemical reaction what species appears at the highest energy?
A. the catalyst
B. the products
C. the reactants
D. the transition state