Section 20.2
Balancing Redox Equations
Practice Test
1.
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.
2NO
2
b.
3NO
2
c.
2NO
3
d.
3NO
3
Hint
2.
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.
-8
b.
-7
c.
7
d.
8
Hint
3.
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.
1
b.
2
c.
3
d.
4
Hint
4.
When the following equation is balanced what is the coefficient of Sn?
Sn + HNO
3
→ SnO
2
+ NO
2
+ H
2
O
a.
1
b.
2
c.
3
d.
4
Hint
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)
a.
5
b.
1
c.
8
d.
4
Hint
