Electrochemistry
Practice Test
1.
Under standard conditions, which of the following is the net reaction that occurs in the cell? Cd|Cd
2+
|| Cu
2+
|Cu
a.
Cu
2+
+ Cd → Cu + Cd
2+
b.
Cu + Cd
2+
→ Cd + Cu
2+
c.
Cu
2+
+ Cd
2+
→ Cu + Cd
d.
Cu + Cd → Cu
2+
+ Cd
2+
2.
Why are alkaline dry cell batteries smaller in size than zinc-carbon dry cells?
a.
No zinc is reduced in the alkaline batteries.
b.
Alkaline batteries do not need the carbon rod cathode.
c.
Alkaline batteries do not require steel cases.
d.
Zinc paste takes up less space than zinc powder.
3.
How does paint protect steel surfaces from corrosion?
a.
Paint prevents the oxidation-reduction reaction of corrosion from occurring.
b.
Paint acts as a sacrificial anode.
c.
Paint galvanizes steel.
d.
Paint corrodes leaving steel intact.
4.
Why is electrolysis needed to produce pure metals?
a.
Metals are always neutral.
b.
Metals would rather be cations.
c.
Metals are easily reduced.
d.
Metals would rather be anions.
5.
The use of electric energy to bring about a chemical reaction is ____________.
a.
a galvanic cell
b.
corrosion
c.
spontaneous combustion
d.
electrolysis
6.
What is the anode reaction when a NiCad battery is used to generate electric current?
a.
reduction of cadmium in the presence of a base
b.
oxidation of cadmium in the presence of an acid
c.
oxidation or cadmium in the presence of a base
d.
reduction of cadmium in the presence of an acid
7.
A cell is constructed by immersing a strip of lead in a 1.0
M
Pb(NO
3
)
2
solution and a strip of silver in a 1.0
M
AgNO
3
solution. The circuit is completed by a wire and a salt bridge. As the cell operates, the strip of silver gains mass (only silver), the strip of lead loses mass, and the concentration of lead ions increases in the solution around the lead strip. Which of the following represents the reaction that occurs at the cathode in this cell?
a.
Ag
+
+ e
-
→ Ag
b.
Ag → Ag
+
+ e
-
c.
Pb → Pb
2+
+ 2e
-
d.
Pb
2+
+ 2e
-
→ Pb
8.
In any electrochemical cell, the cathode is the ________.
a.
positive electrode
b.
negative electrode
c.
electrode at which some species gains electrons
d.
electrode at which some species loses electrons
9.
In an electrolytic cell, the electrode that acts as a source of electrons to the solution is called the __________; the chemical change that occurs at this electrode is called ________.
a.
cathode, oxidation
b.
anode, oxidation
c.
anode, reduction
d.
cathode, reduction
10.
A redox reaction that is not easily reversed is the source of electric energy in a(n) _______.
a.
secondary battery
b.
fuel cell
c.
electrolytic cell
d.
primary battery
11.
Which of the following is not obtained from the electrolysis of an aqueous solution of sodium chloride?
a.
H
2
b.
Na
c.
Cl
2
d.
NaOH
12.
A redox reaction that is easily reversed, can produce electric energy, and can be recharged is a(n) __________.
a.
fuel cell
b.
electrolytic cell
c.
primary battery
d.
secondary battery
13.
During the electrolysis of molten sodium iodide, sodium ions move ________.
a.
to the cathode, which is positively charged
b.
to the cathode, which is negatively charged
c.
to the anode, which is positively charged
d.
to the anode, which is negatively charged
14.
Which of the following must be true of a salt bridge?
a.
The solutions joined by the salt bridge can mix freely.
b.
Ions can move through the salt bridge.
c.
The tube of the salt bridge must remain open.
d.
The salt bridge must prevent the flow of charged particles.
15.
Using a table of standard reduction potentials, which of the following is the strongest oxidizing agent?
a.
F
-
b.
Al
c.
F
2
d.
Al
3+
