Name: _________________________
Balancing Redox Reactions
Part A: Balance the following equations using Oxidation Numbers. Underline the oxidizing agent and circle the
reducing agent
1.
H2S +
HNO3 
2.
H2SO4 + HBr  SO2 +
3.
H2SO4 + HI 
H2S +
I2 +
4.
N 2O +
H2O +
NH3
5.
K+
6.
Fe2O3 +
7.
NH3 +
8.
N2H4 +
9.
NO2 +
H2O 
HNO3 +
10.
MnO2 +
HBr 
Br2 +
MnBr2 +
11.
HClO4 +
ClO2 +
H2O 
HClO3
12.
PbO2 +
NaOH 
PbO +
13.
KMnO4 +
14.
P4 +
H2 
S8 +
KNO3 
NO +
H2O2 
HCl 
H2O +
H2O
K2O
Fe +
O2 
H2O
Br2 + H2O
N2 +
S
Sb +
NO +
SO2
H2O
HNO3 +
Hint: N is in the +2 state
NO
MnCl2 +
HNO3 
H2O
Cl2 +
H3PO4 +
H2O
NaSbO2 +
KCl +
NO
H2O
H2O
Name: _________________________
Part B: Balance the following equations using the Ion-Electron Method for reactions occuring in acidic
solution:
-
2+
15.
Cu + NO3  Cu + NO
16.
MnO4 + H2S  Mn + S
17.
As2O3 + NO3  H3AsO4 + N2O3
18.
Zn + NO3  Zn + NH4
19.
NO2  NO3 + NO
20.
H2O2 + Cr  Cr2O7
21.
Cr2O7 + I  Cr + I3
22.
ClO3 + Cl  Cl2 + ClO2
23.
MnO4 + C2O4  CO2 + Mn
24.
Cr2O7 + Cl  Cr + Cl2
-
2+
-
-
2+
+
-
3+
2-
-
-
3+
2-
-
-
-
2-
2-
-
3+
2+
Name: _________________________
Part C: Balance the following equations using the Ion-Electron Method for reactions occurring in basic
solution:
-
-
25.
Al + OH  AlO2 + H2 (Drano)
26.
Cu(NH3)4 + S2O4  SO3 + Cu + NH3
27.
NO2  NO3 + NO2
28.
Cl2  ClO3 + Cl
29.
MnO4 + C2O4  CO2 + MnO2
30.
Zn + NO3  Zn(OH)4 + NH3
31.
ClO2  ClO2 - + ClO3 –
32.
Br2 (l)  BrO3-(aq) + Br- (aq)
33.
Pb(OH)42- (aq) + ClO- (aq)  PbO2 (s) + Cl- (aq)
34.
H2O2 (aq) + Cl2O7 (aq)  ClO2- (aq) + O2 (g)
35.
H2O2 (aq) + ClO2 (aq)  ClO2- (aq) + O2 (g)
2+
2-
-
-
-
2-
-
-
2-
-
2-