Copyright © 2008 Pearson
Prentice Hall, Inc.
Balancing Redox Reactions: The
Half-Reaction Method
•Add the two
balanced half-reactions together and cancel species that appear on both sides of the equation.
IO31-(aq) +
6H1+(aq)
6e- + 3H2O(l) +
I1-(aq)
2Cr3+(aq) +
7H2O(l) + 6e-
14H1+(aq) +
Cr2O72-(aq)
oxidation:
reduction:
IO31-(aq) +
2Cr3+(aq) +
4H2O(l)
8H1+(aq) + I1-(aq) + Cr2O72-(aq)