Download Chapter 18 review

Name: ______________________
Class: _________________
Date: _________
ID: A
Chpt 18 review
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____
1. What does a chemical reaction rate measure?
a. the amount of reactant used
b. energy change per unit of time
c. change in amount of reactant per unit of time
d. the amount of time needed for the reaction to come to completion
____
2. At
a.
b.
c.
d.
____
3. Why does a higher concentration make a reaction faster?
a. Higher concentration increases the frequency of collisions.
b. Higher concentration increases the total energy of collisions.
c. Higher concentration decreases the activation energy of the overall reaction.
d. Higher concentration decreases the energy needed for a collision to be effective.
____
4. What happens to a catalyst during a reaction?
a. It is unchanged by the reaction.
b. It replaces one of the reactants.
c. It is incorporated into the products.
d. It loses energy to the products.
____
5. Which of the following substances act as catalysts in the body?
a. carbohydrates
b. nucleic acids
c. lipids
d. enzymes
____
6. If a reaction is reversible, what are the relative amounts of reactant and product at the end of the
reaction?
a. no reactant; all product
b. no product; all reactant
c. some product; some reactant
d. The relationship between reactants and products cannot be determined.
____
7. What happens to a reaction at equilibrium when more reactant is added to the system?
a. The reaction makes more products.
b. The reaction makes more reactants.
c. The reaction is unchanged.
d. The answer cannot be determined.
what stage of a chemical reaction is chemical energy at its highest level?
when only reactants are present
when only products are present
when an activated complex exists
when the activated complex becomes a product
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Name: ______________________
____
____
ID: A
8. Which of the changes listed below would shift the following reaction to the right?
4HCl(g) + O 2 (g)
2Cl 2 (g) + 2H 2 O(g)
a.
addition of Cl 2
b.
removal of O 2
c.
d.
increase of pressure
decrease of pressure
9. What is the effect of adding more water to the following equilibrium reaction?
CO 2 + H 2 O
H 2 CO 3
a.
More H 2 CO 3 is produced.
b.
CO 2 concentration increases.
c.
d.
The equilibrium is pushed in the direction of reactants.
There is no effect.
____ 10. What is the equilibrium constant for the following reaction?
C + O2
CO 2
a.
b.
[C][O 2 ]
[CO 2 ]
[CO 2 ]
[C][O 2 ]
2
c.
d.
[C] [O 2 ]
[CO 2 ]
2
[CO 2 ]
2
2
[C] [O 2 ]
2
2
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____ 11. Which statement is true for an equilibrium reaction with a K eq of 1 × 10 ?
a.
b.
c.
d.
The
The
The
The
reactants are favored.
reaction is spontaneous.
products are favored.
reaction is exothermic.
−7
____ 12. If K eq = 4 × 10 , which of the following is true?
a.
b.
c.
d.
Reactants are favored.
Products are favored.
Reactants and products are present in equal amounts.
There are no reactants remaining.
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Name: ______________________
ID: A
____ 13. Which one of the following systems has the highest entropy?
a. 10 mL of water at 10°C
b. 10 mL of water at 50°C
c. 10 mL of water at 100°C
d. All have the same entropy because all are water.
____ 14. The Ks p of Ca(OH)2 is 6.5 × 10-6 and Ca(NO3 ) 2 is a soluble compound. How does the addition of calcium
nitrate to a saturated solution of calcium hydroxide affect the pH of the solution?
a. pH increases.
b. pH decreases.
c. pH is not affected.
d. There is not enough information to relate addition of Ca(NO3 ) 2 to pH change.
____ 15. Which reaction results in the greatest increase in entropy?
a. A → B
b. A → 2B
c. 2A → B
d. 3A → B
____ 16. When a student in a chemistry lab combines two clear solutions a precipitate forms. What conclusion can
the student make about the combined solution?
a. The value of Ks p for the compound formed by the combination of two ions is less
than 1.
b. The value of Ks p for the compound formed by the combination of two ions is greater
than 1.
c. The concentration of one of the ions in solution exceeded the Ks p for that ion in
water.
d. The product of the concentrations of two ions exceeded the Ks p for the compound
formed by the ions.
____ 17. Which of the following statements is true?
a. All spontaneous processes are exothermic.
b. All nonspontaneous processes are endothermic.
c. All spontaneous processes release free energy.
d. Entropy always increases in a spontaneous process.
____ 18. Which of the following is always true of a spontaneous reaction?
a. It is exothermic.
b. It takes place at a rapid rate.
c. It results in increased disorder of the system.
d. It releases free energy.
____ 19. Which of the following is true about the combustion of carbon?
a. The reaction is spontaneous.
b. The reaction is endothermic.
c. Enthalpy remains constant.
d. Entropy decreases.
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Name: ______________________
ID: A
____ 20. What determines whether or not a reaction is spontaneous?
a. change in molar volume and heat change
b. change in enthalpy only
c. enthalpy change and entropy change
d. change in entropy only
____ 21. What is the rate law for the following reaction?
A + 2B → C + D
a. rate = k[A][B]
2
b. rate = k[A] [B]
2
c. rate = k[A][B]
2
2
d. rate = k[A] [B]
____ 22. What is the overall rate order of the following reaction?
A + 2B → C + D
a. zero
b. first
c. second
d. third
____ 23. In a first-order reaction, how does the rate change if the concentration of the reactant decreases to
one-third its original value?
a. The rate decreases by a factor of one-ninth.
b. The rate decreases by a factor of one-third.
c. The rate decreases by a factor of one-half.
d. The rate stays the same.
____ 24. Which of the following statements is true of an elementary reaction?
a. An elementary reaction has only elements as reactants.
b. An elementary reaction has only elements as products.
c. An elementary reaction never needs a catalyst.
d. An elementary reaction converts reactants to products in a single step.
____ 25. What is the shape of the graph of energy vs. reaction progress for a complex reaction?
a. a flat line
b. a single peak
c. several hills and valleys
d. a step-like series of flat lines
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ID: A
Chpt 18 review
Answer Section
MULTIPLE CHOICE
1. ANS: C
PTS: 1
DIF: L1
REF: p. 595
OBJ: 18.1.1 Describe how to express the rate of a chemical reaction.
BLM: knowledge
2. ANS: C
PTS: 1
DIF: L2
REF: p. 597
OBJ: 18.1.1 Describe how to express the rate of a chemical reaction.
BLM: comprehension
3. ANS: A
PTS: 1
DIF: L2
REF: p. 598
OBJ: 18.1.2 Identify four factors that influence the rate of a chemical reaction.
BLM: comprehension
4. ANS: A
PTS: 1
DIF: L1
REF: p. 599
OBJ: 18.1.2 Identify four factors that influence the rate of a chemical reaction.
BLM: knowledge
5. ANS: D
PTS: 1
DIF: L2
REF: p. 601
OBJ: 18.1.2 Identify four factors that influence the rate of a chemical reaction.
BLM: comprehension
6. ANS: C
PTS: 1
DIF: L2
REF: p. 609
OBJ: 18.3.1 Describe what happens at the molecular level in a chemical system at equilibrium.
BLM: comprehension
7. ANS: A
PTS: 1
DIF: L2
REF: p. 612 | p. 613
OBJ: 18.3.2 Identify the three stresses that can cause a change in the equilibrium position of a chemical
system.
BLM: comprehension
8. ANS: C
PTS: 1
DIF: L2
REF: p. 614
OBJ: 18.3.2 Identify the three stresses that can cause a change in the equilibrium position of a chemical
system.
BLM: application
9. ANS: A
PTS: 1
DIF: L2
REF: p. 614
OBJ: 18.3.2 Identify the three stresses that can cause a change in the equilibrium position of a chemical
system.
BLM: application
10. ANS: B
PTS: 1
DIF: L2
REF: p. 616
OBJ: 18.3.3 Describe what the size of an equilibrium constant indicates about a system at equilibrium.
BLM: application
11. ANS: C
PTS: 1
DIF: L2
REF: p. 616
OBJ: 18.3.3 Describe what the size of an equilibrium constant indicates about a system at equilibrium.
BLM: comprehension
12. ANS: A
PTS: 1
DIF: L2
REF: p. 616
OBJ: 18.3.3 Describe what the size of an equilibrium constant indicates about a system at equilibrium.
BLM: comprehension
13. ANS: C
PTS: 1
DIF: L2
REF: p. 631
OBJ: 18.5.2 Identify the part entropy plays in a chemical reaction.
BLM: application
14. ANS: A
PTS: 1
DIF: L3
REF: p. 625
OBJ: 18.4.2 Predict whether a precipitation will occur when two solutions are mixed.
BLM: synthesis
1
ID: A
15. ANS:
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BLM:
16. ANS:
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BLM:
17. ANS:
OBJ:
BLM:
18. ANS:
OBJ:
BLM:
19. ANS:
OBJ:
BLM:
20. ANS:
OBJ:
BLM:
21. ANS:
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BLM:
22. ANS:
OBJ:
BLM:
23. ANS:
OBJ:
BLM:
24. ANS:
OBJ:
BLM:
25. ANS:
OBJ:
BLM:
B
PTS: 1
DIF: L2
REF: p. 631
18.5.2 Identify the part entropy plays in a chemical reaction.
application
D
PTS: 1
DIF: L2
REF: p. 626
18.4.2 Predict whether a precipitation will occur when two solutions are mixed.
comprehension
C
PTS: 1
DIF: L2
REF: p. 633
18.5.3 Identify the two factors that determine whether a reaction is spontaneous.
comprehension
D
PTS: 1
DIF: L2
REF: p. 633
18.5.3 Identify the two factors that determine whether a reaction is spontaneous.
comprehension
A
PTS: 1
DIF: L2
REF: p. 633
18.5.3 Identify the two factors that determine whether a reaction is spontaneous.
application
C
PTS: 1
DIF: L1
REF: p. 632
18.5.3 Identify the two factors that determine whether a reaction is spontaneous.
knowledge
C
PTS: 1
DIF: L2
REF: p. 605
18.2.1 Identify what information a rate law provides about a reaction.
analysis
D
PTS: 1
DIF: L2
REF: p. 605
18.2.1 Identify what information a rate law provides about a reaction.
application
B
PTS: 1
DIF: L2
REF: p. 606
18.2.1 Identify what information a rate law provides about a reaction.
application
D
PTS: 1
DIF: L1
REF: p. 607
18.2.2 Describe how most reactions progress from start to finish.
knowledge
C
PTS: 1
DIF: L1
REF: p. 607
18.2.2 Describe how most reactions progress from start to finish.
comprehension
2