Review Questions: Acids, Bases and Salts
1. How does the Arrhenius Theory define an acid and a base?
a. Acid- Any substance that releases hydrogen ions (H+1) to solution
b. Base- Any substance that releases hydroxide ions (OH-1) to solution
2. How does the Bronsted-Lowry Theory define an acid and a base?
a. Acid- A proton donor or any positive ion (since they have more protons
than electrons)
b. Base- A proton acceptor or any negative ion (since they have more
electrons than protons)
3. How does the Lewis Theory define an acid and a base?
a. Acid- An electron pair acceptor (substance attracted to a pair of electrons)
b. Base- An electron pair donor (substance with a non-metal that has at least
one pair of electrons)
3. What is the molecular formula of the hydronium ion?
4. List some of the common physical and chemical characteristics of acids.
Sour or tart taste
Corrosive to metals releasing hydrogen gas
pH of less than 7
Neutralize bases to form a salt and water
Have a texture similar to water
Changes the color of indicators:
Phenolphthalein turns clear
Litmus paper turns pink
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5. List some of the common physical and chemical characteristics of bases.
Have a bitter taste
pH of greater than 7
Neutralize acids to form a salt and water
Have a texture similar to oil (slippery to the touch)
Changes the color of indicators:
Phenolphthalein turns pink
Litmus paper turns blue
6. What is the definition of a binary acid?
An acid that contains hydrogen and one other nonmetal element
HCl, H2S, H3P, etc.
Name using both a prefix of HYDRO - and suffix of –IC ACID
7. What is the definition of a polyatomic acid?
An acid that contains hydrogen and more than one nonmetal element
H2SO4 , H3PO4 , H2CO3 , etc.
Name using ONLY a suffix of –OUS ACID or –IC ACID (no prefix)
8. Name the following acids given their chemical formulas.
a. HF
Hydrofluoric acid
Binary acid: prefix (hydro) and suffix (-ic acid)
b. H3PO4 Phosphoric acid
Polyatomic acid with an –ate ion; suffix (-ic acid)
c. H2SO3 Sulfurous acid
Polyatomic acid with an –ite ion; suffix (-ous acid)
d. H2CO3 Carbonic acid
Polyatomic acid with an –ate ion; suffix (-ic acid)
e. HBr Hydrobromic acid
Binary acid: prefix (hydro) and suffix (-ic acid)
f. HNO3 Nitric acid
Polyatomic acid with an –ate ion; suffix (-ic acid)
g. HIO2 Iodous acid
Polyatomic acid with an –ite ion; suffix (-ous acid)
h. HBrO3 Bromic acid
i. H2S Hydrosulfuric acid
Polyatomic acid with an –ate ion; suffix (-ic acid)
Binary acid: prefix (hydro) and suffix (-ic acid)
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9. Write the correct chemical formula for the following acids.
a. Hydrochloric acid HCl
(has a hydro prefix and -ic acid suffix) Binary acid
b. Acetic acid HC2H3O2
(acid with an –ic suffix) Polyatomic with –ate ion
c. Sulfuric acid H2SO4
(acid with an –ic suffix) Polyatomic with –ate ion
d. Phosphorous acid H3PO3 (acid with an –ous suffix) Polyatomic with –ite ion
e. Hydroiodic acid
f. Nitrous acid
(has a hydro prefix and –ic acid suffix)
HI
Binary acid
(acid with an –ous suffix) Polyatomic with –ite ion
HNO2
(acid with an –ic suffix) Polyatomic with –ate ion
g. Iodic acid HIO3
h. Bromous acid HBrO2
(acid with an –ous suffix) Polyatomic with –ite ion
i. Oxalic acid
(acid with an –ic suffix) Polyatomic with –ate ion
H2C2O4
10. Name the following bases given their chemical formulas.
a. KOH
Potassium Hydroxide
b. Mg(OH)2 Magnesium Hydroxide
c. Al(OH)3
Aluminum Hydroxide
d. Fe(OH)2
Iron (II) Hydroxide
(two OH-1 ions needed so Fe has a +2 charge
11. Write the correct chemical formula for the following bases.
a. Lithium hydroxide
LiOH
b. Barium hydroxide
Ba(OH)2
c. Copper (I) hydroxide CuOH
d. Zinc hydroxide
e. Sodium hydroxide
Zn(OH)2
NaOH
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12. What is a conjugate base?
What remains or is produced after an acid has released or given away a
hydrogen ion.
13. What is a conjugate acid?
What is produced after a base has accepted or taken a hydrogen ion.
14. In the following reactions, identify the acid, the base, the conjugate acid, and the
conjugate base.
a.
H3PO4
+
OH-1
H2PO4-1
+
H2O
b.
NO2-1
+
H3O+1
HNO2
+
H2O
c.
NH4+1
+
H3O+1
+
H2O
NH3
15. What is the conjugate acid of HSO4-1 ?
16. What is an amphiprotic substance?
A substance that can act as either an acid or a base.
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17. What is the definition of a salt?
A compound that releases + and – ions into a solution that are NOT H+1 or OH-1
This is a physical process.
18. What is dissociation as it applies to salts?
The process by which the + and – ions of a salt separate from each other when
dissolved in water
19. What is ionization?
The formation of ions when neutral molecules like acids and bases react with
water.
This is a chemical process
20. Explain the difference between electrolytes and nonelectrolytes.
a. Electrolytes- Substances that form ions in solution allowing an electric
current to flow through the solution
b. Nonelectrolytes- Substances that DO NOT form ions in solution
21. What is the difference between a strong electrolyte and a weak electrolyte?
a. Strong electrolyte-
Those that ionize almost 100%, releasing lots of ions
into solution.
b. Weak electrolyte-
Those that ionize very little, releasing very few ions into
solution
22. Classify the following acids as either strong acids or weak acids by writing the word
strong or weak below each molecular formula.
HCl
H2CO3
H2O
H2SO4
H3PO4
Strong
Weak
Weak
Strong
Weak
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23. Classify the following bases as either strong bases or weak bases by writing the word
strong or weak below each molecular formula.
NaOH
Ca(OH)2
Strong
Strong
CuOH
Fe(OH)3
Weak
Weak
KOH
Strong
24. How are most salts produced?
By reacting an acid with a base; by a neutralization reaction.
25. Describe the type of salt produced when the following acids and bases react with each
other.
a. Strong acid with a weak base-
Acidic salt
b. Strong acid with a strong base-
Neutral salt
c. Weak acid with a strong base-
Basic salt
26. What is the pH scale?
A relative scale that represents the level of acidity of a solution by the
measurement of the hydrogen ion concentration of a solution.
27. What is the mathematical formula used to calculate the pH of a solution?
pH = - log [H+1]
28. Calculate the pH of each of the following solutions given the hydrogen ion
concentration.
a. [H+1] = 1 x 10-4
4
b. [H+1] = 1 x 10-8
8
c. [H+1] = 1 x 10-6
6
29. Calculate the hydrogen ion concentration of the following solutions given the pH
value of the solution.
a. pH = 3
1 x 10-3
b. pH = 7
1 x 10-7
c. pH = 9
1 x 10-9
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30. What is the pH of a solution with a hydrogen ion concentration of 5 x 10-4?
pH = - log [5 x 10-4]
= 3.3
31. What is a chemical indicator?
A substance that changes color at different pH values.
32. What will be the color of the following indicators in an acidic and basic solution?
Indicator
Color in an acidic solution
Color in a basic solution
Phenolphthalein
Clear
Pink
Litmus
Pink
Blue
33. What is a buffer?
A mixture of substances that resists changes in pH when small amounts of acids
or bases are added.
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