Chapter 20:
Redox Reactions
Practice Test
1.
The highest possible oxidation number for carbon is ________.
a.
6
b.
4
c.
2
d.
8
Hint
2.
Which of the following types of reactions do not usually involve redox?
a.
single-replacement
b.
double-replacement
c.
synthesis
d.
decomposition
Hint
3.
What is the oxidation number of O in Na
2
SO
4
?
a.
2
b.
1
c.
6
d.
-2
Hint
4.
In the following reaction, which chemical species is the oxidizing agent?
5H
2
O
2
+ 2MnO
4
-
+ 6H
+
→ 2Mn
+2
+ 8H
2
O + 5O
2
a.
Mn
2+
b.
H
2
O
2
c.
MnO
4
-
d.
H
+
Hint
5.
Group 1A metal ions have an oxidation number of _______.
a.
2
b.
1
c.
-1
d.
3
Hint
6.
Complete and balance the following redox equation. When properly balanced with whole—number coefficients, the coefficient of S is _________.
H
2
S + HNO
3
→ S + NO + H
2
O
a.
2
b.
3
c.
4
d.
1
Hint
7.
What element is oxidized in the following reaction?
3Cu + 8HNO
3
→ Cu(NO
3
)
2
+ 2NO + 4H
2
O
a.
N
b.
O
c.
H
d.
Cu
Hint
8.
Which species is the reducing agent in the following set of half-reactions?
Cu
2+
+ 2e
-
→ Cu Pb → Pb
2+
+ 2e
-
a.
Pb
b.
Cu
c.
Cu
2+
d.
Pb
2+
Hint
9.
Which of the following reactions is a redox reaction?
a.
2Al(s) + 3H
2
SO
4
(aq)
Al
2
(SO
4
)
3
(aq) + 3H
2
(g)
b.
H
+
(aq) + OH
-
(aq)
H
2
O(l)
c.
CaBr
2
(aq) + H
2
SO
4
(aq)
CaSO
4
(s) + 2HBr(aq)
d.
2KBr(aq) + Pb(NO
3
)
2
(aq)
2KNO
3
(aq) + PbBr
2
(s)
Hint
10.
What is the oxidizing agent in the following reaction?
6KOH(aq) + 3Cl
2
(g) → KClO
3
(aq) + 5KCl(aq) + 3H
2
O(l)
a.
Cl
2
b.
KCl
c.
KClO
3
d.
KOH
Hint
11.
Balance the following ionic equation. What is the coefficient of the reducing agent in this reaction?
Fe
2+
(aq) + MnO
4
-
(aq) + H
+
(aq) → Fe
3+
(aq) + Mn
2+
(aq) + H
2
O(l)
a.
4
b.
1
c.
8
d.
5
Hint
12.
The most electronegative atom in a compound has a charge that is __________.
a.
negative
b.
neutral
c.
positive
d.
zero
Hint
13.
What is the net change in oxidation number of iodine in the following ionic reaction? 2MnO
4
-
+ I
-
+ H
2
O → 2MnO
2
+ IO
3
-
+ 2OH
-
a.
3
b.
6
c.
1
d.
2
Hint
14.
When an atom undergoes oxidation, the ___________ changes.
a.
isotope
b.
identity
c.
mass
d.
charge
Hint
15.
What is the oxidation number of N in KNO
3
?
a.
5
b.
3
c.
-3
d.
6
Hint
16.
A balanced reaction that shows only the oxidation process is a ___________.
a.
single-replacement reaction
b.
synthesis reaction
c.
balanced chemical equation
d.
half-reaction
Hint
17.
Complete and balance the following chemical reaction with the smallest set of coefficients. What is the coefficient for iodine in this reaction?
HI + HNO
3
→ I
2
+ NO + H
2
O
a.
4
b.
3
c.
2
d.
1
Hint
18.
Oxidation is __________.
a.
the gain of electrons and a decrease in charge
b.
the loss of electrons and an increase in charge
c.
the gain of electrons and an increase in charge
d.
the loss of electrons and a decrease in charge
Hint
19.
Predict the products of the following single-replacement reaction.
Fe(s) + CuSO
4
(aq) → ?
a.
FeCuSO
4
b.
Fe(s) + Cu(s) + SO
4
(aq)
c.
Cu(s) + FeSO
4
(aq)
d.
CuS(s) + Fe
2
SO
4
(aq)
Hint
20.
In a redox reaction, the number of electrons lost by the reducing agent ____________.
a.
equals the number of electrons lost by the oxidizing agent
b.
equals the number of electrons gained by the oxidizing agent
c.
equals the number of protons in the reducing agent
d.
equals the number of protons in the oxidizing agent
Hint
