Download 2011-2012 ACAD REVIEW SHEET Chapter 16

Name:
Date:
Period:
ACADEMIC Chapter 16 Review Sheet
Vocabulary
reversible reaction
chemical equilibrium
law of mass action
equilibrium constant
equilibrium expression
law of chemical equilibrium
equilibrium position
homogeneous equilibria
heterogeneous equilibria
reaction quotient
Le Chatelier’s principle
Haber process
Section 16-1
1.
2.
3.
4.
5.
What is the relationship between concentration and rate?
True or False. At equilibrium, the concentrations of reactants and products remain constant which
means that the reaction has stopped.
What are three factors that control the rate of reaction?
Can all reversible reactions be observed in the laboratory? Why or why not?
Why is chemical equilibrium referred to as a dynamic equilibrium?
Section 16-2
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
What do the brackets mean in the equilibrium expression?
If the Keq for the forward reaction is 5, what is the Keq’ for the reverse reaction?
Write the equilibrium expression for 2 NO2(g)  N2O4(g). Make sure you write “Keq =” and
there is no plus sign in the equilibrium constant expression.
Write the equilibrium expression for 2 CO(g) + O 2(g)  2 CO2(g).
What does it mean if the Keq is much greater than 1?
What does it mean if the Keq is much smaller than 1 (like 0.001)?
What does it mean if the Keq is around 1?
Write the equilibrium expression for KCl(l) + Na(l)  NaCl(l) + K(g). NOTE: liquids and solids
are not included in the equilibrium expression.
Write the equilibrium expression for 2 NO(g) + 2 H 2(g)  N2(g) + 2 H2O(l).
At 340C, Keq = 0.064 for the reaction Fe2O3(s) + 3H2(g)  2Fe(s) + 3H2O(g). Given the [H2] =
0.45 M and [H2O] = 0.37 M, find Q and predict how the reaction will proceed.
Ammonia is synthesized from nitrogen and hydrogen in the reaction N 2(g) + 3H2(g)  2NH3(g).
At 500C, the equilibrium constant for this reaction is 0.080. Given that [NH3] = 0.0596 M, [N2]
= 0.600 M, and [H2] = 0.420 M, find Q and predict how the reaction will proceed.
How is the reaction quotient related to the equilibrium constant? In other words, how are they
different, the same?
Section 16-3
18. How does the reaction shift to reestablish equilibrium if you add more CO to the system in the
following reaction: 2 CO(g) + O2(g)  2 CO2(g)?
19. How does the reaction shift to reestablish equilibrium if you take away CO to the system in the
following reaction: 2 CO(g) + O2(g)  2 CO2(g)?
20. How does the reaction shift to reestablish equilibrium if you add more CO 2 to the system in the
following reaction: 2 CO(g) + O2(g)  2 CO2(g)?
21. How does the reaction shift to reestablish equilibrium if you take away CO2 to the system in the
following reaction: 2 CO(g) + O2(g)  2 CO2(g)?
22. How does the reaction shift to reestablish equilibrium if you increase the pressure in the following
reaction: 2 CO(g) + O2(g)  2 CO2(g)?
23. How does the reaction shift to reestablish equilibrium if you increase the temperature in the
following reaction: NH4Cl(s)  NH3(g) + HCl(g) where the H is negative.?
24. Describe Le Chatelier’s principle.
25. What factors alter the equilibrium position in chemical reactions?
Name:
Date:
Period:
ACADEMIC Chapter 16 Review Sheet
Vocabulary
reversible reaction
chemical equilibrium
law of mass action
equilibrium constant
equilibrium expression
law of chemical equilibrium
equilibrium position
homogeneous equilibria
heterogeneous equilibria
reaction quotient
Le Chatelier’s principle
Haber process
Section 16-1
1.
2.
3.
4.
5.
What is the relationship between concentration and rate? (ANS: The greater the concentration, the
faster the rate.)
True or False. At equilibrium, the concentrations of reactants and products remain constant which
means that the reaction has stopped. (ANS: False)
What are three factors that control the rate of reaction? (ANS: Concentration, temperature and
pressure)
Can all reversible reactions be observed in the laboratory? Why or why not? (ANS: Sometimes
the reverse reaction is so small that it cannot be observed.)
Why is chemical equilibrium referred to as a dynamic equilibrium? (ANS: Dynamic means
changing; it means that even at equilibrium, the reaction continues to proceed.)
Section 16-2
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
What do the brackets mean in the equilibrium expression? (ANS: molarity)
If the Keq for the forward reaction is 5, what is the Keq’ for the reverse reaction? (ANS: 1/5)
Write the equilibrium expression for 2 NO2(g)  N2O4(g). Make sure you write “Keq =” and
there is no plus sign in the equilibrium constant expression. (ANS: Keq = [N2O4]/[NO2]2)
Write the equilibrium expression for 2 CO(g) + O 2(g)  2 CO2(g). (ANS: Keq =
[CO2]2/([CO]2[O2]))
What does it mean if the Keq is much greater than 1? (ANS: The equilibrium favors products.)
What does it mean if the Keq is much smaller than 1 (like 0.001)? (ANS: The equilibrium favors
reactants)
What does it mean if the Keq is around 1? (ANS: There is a lot of both reactants and products.)
Write the equilibrium expression for KCl(l) + Na(l)  NaCl(l) + K(g). NOTE: liquids and solids
are not included in the equilibrium expression. (ANS: Keq = [K])
Write the equilibrium expression for 2 NO(g) + 2 H 2(g)  N2(g) + 2 H2O(l). (ANS: Keq =
[N2]/([NO]2[H2]2))
At 340C, Keq = 0.064 for the reaction Fe2O3(s) + 3H2(g)  2Fe(s) + 3H2O(g). Given the [H2] =
0.45 M and [H2O] = 0.37 M, find Q and predict how the reaction will proceed. (ANS: Q = 0.556
which is greater than Keq therefore the reaction will shift to the REACTANTS to reach
equilibrium.)
Ammonia is synthesized from nitrogen and hydrogen in the reaction N 2(g) + 3H2(g)  2NH3(g).
At 500C, the equilibrium constant for this reaction is 0.080. Given that [NH 3] = 0.0596 M, [N2]
= 0.600 M, and [H2] = 0.420 M, find Q and predict how the reaction will proceed. (ANS: Q =
0.0800 which is equal to the Keq therefore it is already at equilibiurm.)
How is the reaction quotient related to the equilibrium constant? In other words, how are they
different, the same? (ANS: They differ in the time they are measured; K is measured at
equilibrium only and Q is measured at anytime. They are the same with respect to their equation;
they have the same equation.)
Section 16-3
18. How does the reaction shift to reestablish equilibrium if you add more CO to the system in the
following reaction: 2 CO(g) + O2(g)  2 CO2(g)? (ANS: It will shift to PRODUCTS.)
19. How does the reaction shift to reestablish equilibrium if you take away CO to the system in the
following reaction: 2 CO(g) + O2(g)  2 CO2(g)? (ANS: It will shift to REACTANTS.)
20. How does the reaction shift to reestablish equilibrium if you add more CO 2 to the system in the
following reaction: 2 CO(g) + O2(g)  2 CO2(g)? (ANS: It will shift to REACTANTS.)
21. How does the reaction shift to reestablish equilibrium if you take away CO2 to the system in the
following reaction: 2 CO(g) + O2(g)  2 CO2(g)? (ANS: It will shift to PRODUCTS.)
22. How does the reaction shift to reestablish equilibrium if you increase the pressure in the following
reaction: 2 CO(g) + O2(g)  2 CO2(g)? (ANS: It will shift to the PRODUCTS.)
23. How does the reaction shift to reestablish equilibrium if you increase the temperature in the
following reaction: NH4Cl(s)  NH3(g) + HCl(g) where the H is negative? (ANS: It will shift
to the REACTANTS.)
24. Describe Le Chatelier’s principle. (ANS: The reaction will shift to minimize the disturbance to reestablish equilibrium.)
25. What factors alter the equilibrium position in chemical reactions? (ANS: Concentration, Pressure
and temperature)