05_CTR_ch19 7/12/04 8:16 AM Page 487
Name ___________________________
19.1
Date ___________________
Class __________________
ACID-BASE THEORIES
Section Review
Objectives
• Define the properties of acids and bases
• Compare and contrast acids and bases as defined by the theories of Arrhenius,
Brønsted-Lowry, and Lewis
Vocabulary
•
•
•
•
• conjugate base
• conjugate acid–base pair
• hydronium ion (H3O!)
monoprotic acids
diprotic acids
triprotic acids
• amphoteric
• Lewis acid
• Lewis base
conjugate acid
Part A Completion
Use this completion exercise to check your understanding of the concepts and terms
that are introduced in this section. Each blank can be completed with a term, short
phrase, or number.
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Compounds can be classified as acids or bases according to
1
different theories. An
2
acid yields hydrogen ions
in aqueous solution. An Arrhenius base yields
solution. A Brønsted-Lowry acid is a
Lowry base is a proton
6
5
4
3
in aqueous
donor. A Brønsted-
. In the Lewis theory, an acid is an
acceptor. A Lewis base is an electron-pair
7
An acid with one ionizable hydrogen atom is called a
A
8
3.
4.
5.
7
8.
9.
acid.
10
2.
6.
.
acid, while an acid with two ionizable hydrogen atoms is called a
9
1.
is a pair of substances related by the gain or loss of
10.
a hydrogen ion. A substance that can act as both an acid and a base 11.
is called
11
.
Chapter 19 Acids, Bases, and Salts
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Class __________________
Part B True-False
Classify each of these statements as always true, AT; sometimes true, ST; or never true, NT.
________ 12. Hydrochloric acid is a strong acid that is diprotic.
________ 13. The ammonium ion, NH4!, is a Brønsted-Lowry base.
________ 14. A Brønsted-Lowry base is a hydrogen-ion acceptor.
________ 15. A compound can act as both an acid and a base.
________ 16. PBr3 is a Lewis base.
Part C Matching
Match each description in Column B to the correct term in Column A.
Column A
Column B
a. tastes sour and will change the color of an acid-base
indicator
________ 18. triprotic acids
b. an electron-pair donor
________ 19. acid properties
c. a water molecule that gains a hydrogen ion
________ 20. base properties
d. acids that contain three ionizable hydrogens
________ 21. conjugate base
e. particle that remains when an acid has donated a
hydrogen ion
________ 22. conjugate acid
f. an electron-pair acceptor
________ 23. hydronium ion (H3O!)
g. acids that contain one ionizable hydrogen
________ 24. Lewis acid
h. tastes bitter and feels slippery
________ 25. Lewis base
i. particle formed when a base gains a hydrogen ion
Part D Problem
Answer the following in the space provided.
26. Identify the Lewis acid and Lewis base in the following reaction. Explain.
H
H
@ ^O % @
H2C
C2H
@
@
H
H
dimethyl ether
488
Core Teaching Resources
F
H
H @
% ^
C
B2F
^ % ^ %
F
!
uy H
O
^ %
@
F
F
H2C2H
@
H
boron trifluoride
F
@
B
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________ 17. monoprotic acids
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Name ___________________________
Date ___________________
Class __________________
HYDROGEN IONS AND ACIDITY
19.2
Section Review
Objectives
• Classify a solution as neutral, acidic, or basic, given the hydrogen-ion or
hydroxide-ion concentration
• Convert hydrogen-ion concentrations into values of pH and hydroxide-ion
concentrations into values of pOH
• Describe the purpose of pH indicators
Vocabulary
• self-ionization
• neutral solution
• ion-product constant for
water (Kw)
• acidic solution
• basic solution
• alkaline solutions
• pH
Key Equations
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• Kw ! [H"] # [OH$] ! 1.0 # 10$14M 2
• pH ! $ log [H"]
• pOH ! $ log [OH$]
• pH " pOH ! 14
Part A Completion
Use this completion exercise to check your understanding of the concepts and terms
that are introduced in this section. Each blank can be completed with a term, short
phrase, or number.
Water molecules can
1
to form hydrogen ions (H") and
hydroxide ions (OH$). The concentrations of these ions in pure
2
water at 25°C are both equal to
4
denote the
strongly
5
9
6
, 14 is strongly
8
, and 7 is
7
. Pure
4.
5.
6.
7.
.
constant for water has a value of 1.0 # 10$14.
Thus, the product of the concentrations of
11
, is used to
concentration of a solution. On this scale, 0 is
water at 25°C has a pH of
The
3
2.
3.
mol/L.
The pH scale, which has a range from
1.
10
8.
9.
ions and
ions in aqueous solution will always equal 1.0 # 10$14.
10.
11.
Chapter 19 Acids, Bases, and Salts
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Date ___________________
Class __________________
Part B True-False
Classify each of these statements as always true, AT; sometimes true, ST; or never true, NT.
________ 12. In an acidic solution, [H!] is greater than [OH"].
________ 13. pH indicators can give accurate pH readings for solutions.
________ 14. If the [H!] in a solution increases, the [OH"] must decrease.
________ 15. The [OH"] is less than 10"7M in a basic solution.
________ 16. The definition of pH is the negative logarithm of the hydroxide-ion
concentration.
Part C Matching
Match each description in Column B to the correct term in Column A.
Column A
Column B
a. aqueous solution in which [H!] and [OH"] are equal
________ 18. pH
b. product of hydrogen ion and hydroxide ion
concentrations for water
________ 19. self-ionization
c. base solutions
________ 20. neutral solution
d. solution in which [H!] is less than [OH"]
________ 21. ion-product constant
for water (Kw)
e. reaction in which two water molecules produce ions
________ 22. acidic solution
f. the negative logarithm of the hydrogen-ion
concentration
________ 23. basic solution
g. solution in which [H!] is greater than [OH"]
Part D Problems
Answer the following in the space provided.
24. Calculate the hydroxide-ion concentration, [OH"], for an aqueous solution in
which [H!] is 1 # 10"10 mol/L. Is this solution acidic, basic, or neutral?
25. Determine the hydrogen-ion concentrations for aqueous solutions that have
the following pH values.
a. 3
b. 6
c. 10
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Core Teaching Resources
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________ 17. alkaline solutions
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Name ___________________________
19.3
Date ___________________
Class __________________
STRENGTHS OF ACIDS AND BASES
Section Review
Objectives
• Define strong acids and weak acids
• Calculate an acid dissociation constant (Ka) from concentration and
pH measurements
• Order acids by strength according to their acid dissociation constants (Ka)
• Order bases by strength according to their base dissociation constants (Kb)
Vocabulary
• strong acids
• weak acids
• acid dissociation constant (Ka)
• strong bases
• weak bases
• base dissociation constant (Kb)
Part A Completion
© Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved.
Use this completion exercise to check your understanding of the concepts and terms
that are introduced in this section. Each blank can be completed with a term, short
phrase, or number.
1
The strength of an acid or a base is determined by the
2.
of the substance in solution. The acid dissociation constant,
2
, is a quantitative measure of acid strength. A strong acid
has a much
3
Ka than a weak acid. The Ka of an acid is
determined from measured
4
6
solution and are
1 percent ionized, is a
5
ionized in
6.
7.
7
8.
acid. Magnesium hydroxide and
8
9
9.
.
to form the hydroxide ion and
10.
of the base. Concentration in solution does
11.
Weak bases react with
10
4.
acids. Ethanoic acid, which is only about
calcium hydroxide are strong
the conjugate
3.
5.
values.
Hydrochloric acid and sulfuric acid are
1.
not affect whether an acid or a base is
11
or weak.
Chapter 19 Acids, Bases, and Salts
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Part B True-False
Classify each of these statements as always true, AT; sometimes true, ST; or never true, NT.
________ 12. Acids are completely dissociated in aqueous solution.
________ 13. Diprotic acids lose both hydrogens at the same time.
________ 14. Acid dissociation constants for weak acids can be calculated from
experimental data.
________ 15. Bases react with water to form hydroxide ions.
Part C Matching
Match each description in Column B to the correct term in Column A.
Column A
Column B
a. ratio of the concentration of the dissociated (or ionized) form
of an acid to the concentration of the undissociated acid
________ 17. weak acids
b. bases that dissociate completely into metal ions and
hydroxide ions in aqueous solution
________ 18. acid dissociation
constant (Ka)
c. acids that ionize completely in aqueous solution
________ 19. strong bases
d. bases that do not dissociate completely in aqueous solution
________ 20. weak bases
e. acids that are only partially ionized in aqueous solution
________ 21. base dissociation
constant (Kb)
f. ratio of concentration of conjugate acid times concentration
of hydroxide ion to the concentration of conjugate base
Part D Problem
Answer the following in the space provided.
22. A 0.35M solution of a strong acid, HX, has a [H!] of 4.1 " 10#2. What is the value
of Ka for this acid?
492
Core Teaching Resources
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________ 16. strong acids
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Name ___________________________
19.4
Date ___________________
Class __________________
NEUTRALIZATION REACTIONS
Section Review
Objectives
• Explain how acid–base titration is used to calculate the concentration of an acid
or a base
• Explain the concept of equivalence in neutralization reactions
Vocabulary
• neutralization reactions
• equivalence point
• standard solution
• titration
• end point
Key Equations
• Acid ! Base y Salt ! Water
molar mass
number of ionizable hydrogens
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• Gram equivalent mass " $$$$
• Normality (N) " equiv/L
• N1 # V1 " N2 # V2
• NA # VA " NB # VB
Part A Completion
Use this completion exercise to check your understanding of the concepts and terms
that are introduced in this section. Each blank can be completed with a term, short
phrase, or number.
In the reaction of a(n)
and
4
2
1
ions react to produce
, is usually carried out by
with a base, hydrogen ions
3
5
. This reaction, called
. The
6
in a
point of a titration, the number of equivalents of acid
equals the number of equivalents of base.
2.
3.
4.
titration is the point at which the solution is neutral. At the
7
1.
5.
6.
7.
Chapter 19 Acids, Bases, and Salts
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Name ___________________________
Date ___________________
Class __________________
Part B True-False
Classify each of these statements as always true, AT; sometimes true, ST; or never true, NT.
________ 8. A solution of known concentration is called a standard solution.
________ 9. The end point of a titration of a strong base with a strong acid occurs
when [H!] " [OH#].
________ 10. The point of neutralization is the end point of titration.
________ 11. The reaction of an acid and a base produces only water.
Part C Matching
Match each description in Column B to the correct term in Column A.
Column A
Column B
a. when the number of moles of hydrogen ions equals
the number of moles of hydroxide ions
________ 13. neutralization
reactions
b. a solution of known concentration
________ 14. equivalence point
c. a process for determining the concentration of a
solution by adding a known amount of a standard
solution
________ 15. standard solution
d. point of neutralization
________ 16. end point
e. reactions between acids and bases to produce a salt
and water
Part D Problem
Answer the following in the space provided.
17. Complete and balance the equations for the following acid–base reactions.
a. H3PO4 ! Al(OH)3
b. HI ! Ca(OH)2
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Core Teaching Resources
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________ 12. titration
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Name ___________________________
19
Date ___________________
Class __________________
ACIDS, BASES, AND SALTS
Practice Problems
In your notebook, solve the following problems.
SECTION 19.1 ACID–BASE THEORIES
1. Identify the hydrogen ion donor(s) and hydrogen ion acceptor(s) for ionization
of H2SO4 in water. Label the conjugate acid!base pairs.
2. Identify all of the ions that may be formed when H3PO4 ionizes in water.
3. Classify the following acids as monoprotic, diprotic, or triprotic.
a. HCOOH
b. HBr
c. H2SO3
d. H3ClO4
4. What would you expect to happen when lithium metal is added to water? Show
the chemical reaction.
5. In the following chemical reaction, identify the Lewis acid and base.
BF3 " F# 1 BF4#
6. Describe some distinctive properties of acids.
7. Describe some distinctive properties of bases.
SECTION 19.2 HYDROGEN IONS AND ACIDITY
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1. A solution has a hydrogen ion concentration of 1 $ 10#6M. What is its pH?
2. What is the pH of a solution if the [H"] % 7.2 $ 10#9M?
3. What is the pOH of a solution if the [OH#] % 3.5 $ 10#2M?
4. What is the pOH of a solution that has a pH of 3.4?
5. Classify each solution as acidic, basic, or neutral.
a. [H"] % 2.5 $ 10#9M
d. [H"] % 1 $ 10#7M
b. pOH % 12.0
e. pH % 0.8
c. [OH#] % 9.8 $ 10#11M
6. Calculate the pH of each solution.
a. [H"] % 1 $ 10#5M
c. [OH#] % 2.2 $ 10#7M
b. [H"]% 4.4 $ 10#11M
d. pOH % 1.4
7. Classify the solutions in problem 6 as acidic or basic.
8. Why is there a minus sign in the definition of pH?
9. A solution has a pOH of 12.4. What is the pH of this solution?
10. What is the pH of a solution with [H#] % 1 $ 10#3M?
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Class __________________
SECTION 19.3 STRENGTHS OF ACIDS AND BASES
1. Rank 1M of these compounds in order of increasing hydrogen ion
concentration: weak acid, strong acid, strong base, weak base.
2. Write the expression for the acid dissociation constant of the strong acid
hydrofluoric acid, HF.
3. Write the expression for the base dissociation constant for hydrazine, N2H4, a
weak base. Hydrazine reacts with water to form the N2H5! ion.
4. Use Table 19.8 in your textbook to rank these acids from weakest to strongest:
HOOCCOOH, HCO3", H2PO4", HCOOH.
5. Write the equilibrium equation and the acid dissociation constant for the
following weak acids.
a. H2S
b. NH4!
c. C6H5COOH
6. Match each solution with its correct description.
a. dilute, weak acid
(1) 18M H2SO4(aq)
b. dilute, strong base
(2) 0.5M NaOH(aq)
c. concentrated, strong acid
(3) 15M NH3(aq)
d. dilute, strong acid
(4) 0.1M HC2H3O2(aq)
e. concentrated, weak base
(5) 0.1M HCl(aq)
7. Write the base dissociation constant expression for the weak base analine,
C6H5NH2.
C6H5NH2(aq) ! H2O(l) 1 C6H5NH3!(aq) ! OH"(aq)
9. The Ka of benzoic acid, C6H5COOH, is 6.3 $ 10"5. What is the equilibrium [H!]
in a 0.20M solution of benzoic acid?
10. A 0.10M solution of hydrocyanic acid, HCN, has an equilibrium hydrogen ion
concentration of 6.3 $ 10"6M. What is the Ka of hydrocyanic acid?
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8. A 0.10M solution of formic acid has an equilibrium [H!] # 4.2 $ 10"3M.
HCOOH(aq) → H!(aq) ! HCOO"(aq)
What is the Ka of formic acid?
05_CTR_ch19 7/12/04 8:16 AM Page 499
Name ___________________________
Date ___________________
Class __________________
SECTION 19.4 NEUTRALIZATION REACTIONS
1. What is the molarity of a sodium hydroxide solution if 38 mL of the solution is
titrated to the end point with 14 mL of 0.75M sulfuric acid?
2. If 24.6 mL of a Ca(OH)2 solution is needed to neutralize 14.2 mL of 0.0140M
HC2H3O2, what is the concentration of the calcium hydroxide solution?
3. A 12.4 mL solution of H2SO4 is completely neutralized by 19.8 mL of 0.0100M
Ca(OH)2. What is the concentration of the H2SO4 solution?
4. What volume of 0.12M Ba(OH)3 is needed to neutralize 12.2 mL of 0.25M HCl?
5. A 55.0-mg sample of Al(OH)3 is reacted with 0.200M HCl. How many milliters of
the acid are needed to neutralize the Al(OH)3?
SECTION 19.5 SALTS IN SOLUTION
1. A buffer solution is prepared by mixing together equal quantities of formic acid,
HCHO2, and sodium formate, NaCHO2. Write equations that show what happens
when first acid, and then base, is added to this buffer solution.
2. Complete the following rules.
a. strong acid ! strong base y
c. weak acid ! strong base y
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b. strong acid ! weak base y
Chapter 19 Acids, Bases, and Salts
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