Acid & Base Review
1. Which compound is an electrolyte?
A)
C)
11. When the hydronium ion concentration of a solution is increased
by a factor of 10, the pH value of the solution
B)
D)
2. Which laboratory test result can be used to determine if KCl(s) is
an electrolyte?
A)
B)
C)
D)
pH of KCl(aq)
pH of KCl(s)
electrical conductivity of KCl(aq)
electrical conductivity of KCl(s)
A) 1
B) H2O( )
D) OH–(aq)
4. When dissolved in water, an Arrhenius base yields
B) hydronium ions
D) oxide ions
5. According to the Arrhenius theory, a base reacts with an acid to
produce
A) ammonia and methane
C) water and methane
B) ammonia and a salt
D) water and a salt
6. Which compound is an Arrhenius acid?
A) CaO
B) HCI
C) K2O
D) NH3
7. When one compound dissolves in water, the only positive ion
produced in the solution is
H3O+ (aq). This compound is classified as
A) a salt
C) an Arrhenius acid
B) a hydrocarbon
D) an Arrhenius base
8. Given the equation:
Cl–(aq)
HCl(g) + H2O( )
X(aq) +
Which ion is represented by X?
A) hydroxide
C) hypochlorite
B) hydronium
D) perchlorate
C) LiOH
C) 3.0
D) 20
B) 2
C) 3
D) 11
14. The [H3O+] of a solution is 1 × 10–8. This solution has a pH of
A) 6, which is acidic
C) 6, which is basic
B) 8, which is basic
D) 8, which is acidic
15. The H3O+ ion concentration of a solution is 1 × 10–4 mole per
liter. This solution is
A)
B)
C)
D)
acidic and has a pH of 4
acidic and has a pH of 10
basic and has a pH of 4
basic and has a pH of 10
16. Based on the results of testing colorless solutions with
indicators, which solution is most acidic?
A)
B)
C)
D)
a solution in which bromthymol blue is blue
a solution in which bromcresol green is blue
a solution in which phenolphthalein is pink
a solution in which methyl orange is red
17. Which indicator would best distinguish between a solution with
a pH of 3.5 and a solution with a pH of 5.5
A) bromthymol blue
C) litmus
B) bromcresol green
D) thymol blue
18. According to one acid-base theory, a base is an
A)
B)
C)
D)
19. Given the equation representing a reaction at equilibrium:
9. Which substance is an Arrhenius base?
A) CH3OH B) CH3Cl
B) 0.20
13. What is the pH of a 0.001 M HNO3 solution?
NH3(g) + H2O( )
NH4+(aq) + OH–(aq)
According to one acid-base theory, the reactant that donates an H
+ ion in the forward reaction is
A) hydrogen ions
C) hydroxide ions
B) decreases 10 pH units
D) increases 10 pH units
12. A solution with a pH of 2.0 has a hydronium ion concentration
ten times greater than a solution with a pH of
A) 1.0
3. Given the equation representing a reversible reaction:
A) NH3(g)
C) NH4+(aq)
A) decreases 1 pH unit
C) increases 1 pH unit
D) LiCl
10. According to the Arrhenius theory, an acid is a substance that
A) changes litmus from red to blue
B) changes phenolphthalein from colorless to pink
C) produces hydronium ions as the only positive ions in an
aqueous solution
D) produces hydroxide ions as the only negative ions in an
aqueous solution
NH3(g)+ H2O( )
NH4+ (aq) + OH–(aq)
The H+ acceptor for the forward reaction is
A) H2O( )
C) NH4+(aq)
B) NH3(g)
D) OH–(aq)
20. Given the reaction:
HSO4– + HPO4 2– « SO42– + H2PO4
Which pair represents an acid and its conjugate base?
A) HSO4– and SO42–
C) SO42– and H2PO4–
B) HSO4– and HPO42–
D) SO42– and HPO42–
Acid & Base Review
Base your answers to questions 21 and 22 on
the information below and on your knowledge of chemistry.
The pH of various aqueous solutions are shown in the table below.
21. State how many times greater the hydronium ion concentration in the HCl(aq) is than the hydronium ion concentration in
the HC2H3O2(aq).
22. Complete the table by writing the color of thymol blue in the NaCl(aq) and in the NaOH(aq) solutions.
23. Given the reaction:
27. Which word equation represents a neutralization reaction?
H2O + HCl « H3O+ + Cl–
The Brönsted-Lowry base for the forward reaction is
A) H2O
B) HCl
C) H3O+
D) Cl–
24. Which is the conjugate acid of HSO4–?
A) H2SO4 B) H3O+
C) HSO3– D) SO42–
25. Which compound is produced when HCl(aq) is neutralized by
Ca(OH)2(aq)?
A) CaCl2
B) CaH2
C) HClO
D) HClO2
26. Which solution reacts with LiOH(aq) to produce a salt and
water?
A) KCl(aq)
C) NaOH(aq)
B) CaO(aq)
D) H2SO4(aq)
A)
B)
C)
D)
base + acid ® salt + water
base + salt ® water + acid
salt + acid ® base + water
salt + water ® acid + base
28. Which equation represents a neutralization reaction?
A)
B)
C)
D)
4Fe(s) + 3O2(g) ® Fe2O3(s)
2H2(g) + O2(g) ® 2H2O( )
HNO3(aq) + KOH(aq) ® KNO3(aq) + H2O( )
AgNO3(aq) + KCl(aq) ® KNO3(aq) + AgCl(s)
Acid & Base Review
Base your answers to questions 29 and 30 on the information below and on your knowledge of chemistry.
During a laboratory activity, a student places 25.0 mL of HCl(aq) of unknown concentration into a flask. The
student adds four drops of phenolphthalein to the solution in the flask. The solution is titrated with 0.150 M KOH(aq)
until the solution appears faint pink. The volume of KOH(aq) added is 18.5 mL.
29. Complete the equationfor the neutralization reaction that occurs during the titration.
30. Determine the concentration of the HCl(aq) solution, using the titration data.
31. Base your answer to the following question on
the information below.
In a titration, 20.0 milliliters of 0.15 M HCl(aq) is exactly neutralized by 18.0 milliliters of KOH(aq).
Compare the number of moles of H+(aq) ions to the number of moles of OH–(aq) ions in the titration mixture when the
HCl(aq) is exactly neutralized by the KOH(aq).
Base your answers to questions 32 through 34 on the
information below.
Some carbonated beverages are made by forcing carbon dioxide
gas into a beverage solution. When a bottle of one kind of
carbonated beverage is first opened, the beverage has a pH
value of 3.
32. After the beverage bottle is left open for several hours, the
hydronium ion concentration in the beverage solution decreases
to
of the original concentration. Determine the new pH of
the beverage solution.
33. Using Table M, identify one indicator that is yellow in a solution
that has the same pH value as this beverage.
34. State, in terms of the pH scale, why this beverage is classified as
acidic.
Acid & Base Review
Base your answers to questions 35 through 37 on the information below.
In liquid water, an equilibrium exists between H2O( ) molecules, H+(aq) ions, and OH-(aq) ions. A person
experiencing acid indigestion after drinking tomato juice can ingest milk of magnesia to reduce the acidity of the
stomach contents. Tomato juice has a pH value of 4. Milk of magnesia, a mixture of magnesium hydroxide and water,
has a pH value of 10.
35. What is the color of thymol blue indicator when placed in a sample of milk of magnesia?
36. Identify the negative ion found in milk of magnesia.
37. Compare the hydrogen ion concentration in tomato juice to the hydrogen ion concentration in milk of magnesia.
Base your answers to questions 38 through 40 on the information below.
Soil pH can affect the development of plants. For example, a hydrangea plant produces blue flowers when grown in
acidic soil but pink flowers when grown in basic soil. Evergreen plants can show a yellowing of foliage, called chlorosis,
when grown in soil that is too basic.
Acidic soil can be neutralized by treating it with calcium hydroxide, Ca(OH)2, commonly called slaked lime. Slaked
lime is slightly soluble in water.
38. Write an equation, using symbols or words, for the neutralization of the ions in acidic soil by the ions released by slaked
lime in water.
39. An evergreen plant has yellowing foliage. The soil surrounding the plant is tested with methyl orange and bromthymol
blue. Both indicators turn yellow in the soil tests. State, in terms of pH value, why the yellowing of the plant is not due to
chlorosis.
40. Compare the hydrogen ion concentration to the hydroxide ion concentration in soil when a hydrangea plant produces pink
flowers.