Copyright © 2008 Pearson Prentice Hall, Inc.
Chapter 4/
49
Balancing Redox Reactions:
The Oxidation-Number Method
•
Decide which atoms have changed oxidation number,
and by how much.
2
Cr
3+
I
1-
(
aq
) +
O
7
2-
(
aq
)
(
aq
) +
O
3
1-
(
aq
)
I
+5
+3
reduction
Cr
2
-1
+6
oxidation