Redox Reactions
Practice Test
1.
Balance the following equation with the smallest whole—number coefficients. How many moles of zinc will react with 6 moles of cobalt
III
chloride?
Zn
s
+CoCl
3
aq
→ZnCl
2
aq
+Co
s
SC.B.1.4.2
a.
3
b.
2
c.
9
d.
6
2.
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
SC.B.1.4.2
a.
4
b.
1
c.
3
d.
2
3.
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.
6
b.
2
c.
1
d.
3
4.
Determine the net change in oxidation number of chlorine in the following reaction:
ClO
4
-
aq
+ Br
-
aq
→ Cl
-
aq
+ Br
2
g
in acid solution
a.
7
b.
-8
c.
-7
d.
8
5.
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
SC.B.1.4.2
a.
1
b.
8
c.
5
d.
4
6.
The highest possible oxidation number for carbon is ________.
a.
2
b.
6
c.
4
d.
8
7.
Balance the following equation. How many electrons must be transferred between the reducing agent and the oxidizing agent in this reaction?
H
2
S+HNO
3
→S+NO+H
2
0
SC.B.1.4.2
a.
6
b.
2
c.
3
d.
4
8.
Which of the following reactions is a redox reaction?
a.
H
+
aq
+ OH
-
aq
→ H
2
O
l
b.
CaBr
2
aq
+ H
2
SO
4
aq
→ CaSO
4
s
+ 2HBr
aq
c.
2Al
s
+ 3H
2
SO
4
aq
→ Al
2
SO
4
3
aq
+ 3H
2
g
d.
2KBr
aq
+ Pb
NO
3
2
aq
→ 2KNO
3
aq
+ PbBr
2
s
9.
Select the compound in which chlorine has the highest possible oxidation number.
a.
HClO
4
b.
HCl
c.
HClO
3
d.
HClO
10.
Name the spectator ion in the following equation, including the correct coefficient:
Cu
s
+ 4HNO
3
aq
→ Cu
NO
3
2
aq
+ 2NO
2
+ 2H
2
O
l
a.
3NO
2
b.
2NO
2
c.
2NO
3
d.
3NO
3
11.
When the following equation is balanced what is the coefficient of Sn?
Sn +HNO
3
→SnO
2
+NO
2
+H
2
O
SC.B.1.4.2
a.
3
b.
1
c.
4
d.
2
12.
What element is oxidized in the following reaction?
3Cu+8HNO
3
→Cu
NO
3
2
+2NO+4H
2
O
a.
Cu
b.
O
c.
N
d.
H
13.
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
SC.B.1.4.2
a.
1
b.
3
c.
4
d.
2
14.
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.
H
+
b.
MnO
4
-
c.
Mn
2+
d.
H
2
O
2
15.
Which of the following half-reactions represents oxidation?
a.
Fe
3+
+ 3e
-
→ Fe
b.
O
2
+ 4e
-
→ 2O
2-
c.
Cu
2+
+ 2e
-
→ Cu
d.
Fe → Fe
2+
+ 2e
-
