Transcript Balancing Redox Full Reactions in Acid Solution
Electrochemistry Lesson 6 Balancing Redox Reactions
Balancing Redox Full Reactions in Acid Solution
Balancing Redox Full Reactions in Acid Solution
MnO 4 + C 2 O 4 2 → MnO 2 + CO 3 2-
Balancing Redox Full Reactions in Acid Solution
MnO 4 + C 2 O 4 2 → MnO 2 + CO 3 2 1.
Separate into half reactions.
Balancing Redox Full Reactions in Acid Solution
MnO 4 + C 2 O 4 2 → MnO 2 + CO 3 2 1.
2.
Separate into half reactions.
Balance each half reaction.
Balancing Redox Full Reactions in Acid Solution
MnO 4 MnO 4 C 2 O 4 2 + C 2 O 4 2 → MnO 2 + CO 3 2 → MnO 2 → CO 3 2 1.
2.
Separate into half reactions.
Balance each half reaction.
Balancing Redox Full Reactions in Acid Solution
MnO 4 MnO 4 C 2 O 4 2 + C 2 O 4 2 → MnO 2 + CO 3 2 → MnO 2 →
2
CO 3 2 1.
2.
Separate into half reactions.
Balance each half reaction.
Balancing Redox Full Reactions in Acid Solution
MnO 4 MnO 4 C 2 O 4 2 + C 2 O 4 2 → MnO 2 + CO 3 2 → MnO 2 +
2H 2 O
→
2
CO 3 2 1.
2.
Separate into half reactions.
Balance each half reaction.
Balancing Redox Full Reactions in Acid Solution
MnO MnO 4 C 2 O 4 2 4 + + C 2 O 4 2 → MnO 2 + CO 3 2 → MnO 2 +
2H 2 O 2H 2 O
→
2
CO 3 2 1.
2.
Separate into half reactions.
Balance each half reaction.
Balancing Redox Full Reactions in Acid Solution
MnO MnO 4 C 2 O 4 2 4 + C 2 O 4 2 → MnO 2 + CO 3 2 +
4H +
→ MnO 2 +
2H 2 O
+
2H 2 O
→
2
CO 3 2 1.
2.
Separate into half reactions.
Balance each half reaction.
Balancing Redox Full Reactions in Acid Solution
MnO MnO 4 C 2 O 4 2 4 + C 2 O 4 2 → MnO 2 + CO 3 2 +
4H +
→ MnO 2 +
2H 2 O
+
2H 2 O
→
2
CO 3 2 +
4H +
1.
2.
Separate into half reactions.
Balance each half reaction.
Balancing Redox Full Reactions in Acid Solution
MnO 4 + C 2 O 4 2 → MnO 2 + CO 3 MnO 4 C 2 O 4 2 +
4H + + 3e -
→ MnO 2 +
2H 2 O
+
2H 2 O
→
2
CO 3 2 +
4H +
2 1.
2.
Separate into half reactions.
Balance each half reaction.
Balancing Redox Full Reactions in Acid Solution
MnO 4 + C 2 O 4 2 → MnO 2 + CO 3 2 MnO 4 C 2 O 4 2 +
4H + + 3e -
→ MnO 2 +
2H 2 O
+
2H 2 O
→
2
CO 3 2 +
4H + + 2e -
1.
2.
Separate into half reactions.
Balance each half reaction.
Balancing Redox Full Reactions in Acid Solution
MnO 4 + C 2 O 4 2 → MnO 2 + CO 3 2 MnO 4 C 2 O 4 2 +
4H + + 3e -
→ MnO 2 +
2H 2 O
+
2H 2 O
→
2
CO 3 2 +
4H + + 2e -
1.
2.
3.
Separate into half reactions.
Balance each half reaction.
Add the two half reactions.
Balancing Redox Full Reactions in Acid Solution
MnO 4 + C 2 O 4 2 → MnO 2 + CO 3 2-
2
(MnO 4
3
(C 2 O 4 2 +
4H + + 3e -
→MnO 2 +
2H 2 O
) +
2H 2 O
→
2
CO 3 2 +
4H + + 2e -
) 1.
2.
3.
Separate into half reactions.
Balance each half reaction.
Add the two half reactions.
Balancing Redox Full Reactions in Acid Solution
MnO 4 + C 2 O 4 2 → MnO 2 + CO 3 2 2(MnO 4 3(C 2 O 4 2 +
4H + + 3e -
→MnO 2 +
2H 2 O
) +
2H 2 O
→
2
CO 3 2 +
4H + + 2e -
) 2MnO 4 +
8H + +
3C 2 O 4 2 +
6H 2 O
→ 2MnO 2 +
4H 2 O + 6
CO 3 2 +
12H +
1.
2.
3.
Separate into half reactions.
Balance each half reaction.
Add the two half reactions.
Balancing Redox Full Reactions in Acid Solution
1.
2.
3.
4.
MnO 4 + C 2 O 4 2 → MnO 2 + CO 3 2 2(MnO 4 3(C 2 O 4 2 +
4H + + 3e -
→MnO 2 +
2H 2 O
) +
2H 2 O
→
2
CO 3 2 +
4H + + 2e -
) 2MnO 4 +
8H + +
3C 2 O 4 2 +
6H 2 O
→ 2MnO 2 +
4H 2 O + 6
CO 3 2 +
12H +
Separate into half reactions.
Balance each half reaction.
Add the two half reactions.
Simplify
Balancing Redox Full Reactions in Acid Solution
1.
2.
3.
4.
MnO 4 + C 2 O 4 2 → MnO 2 + CO 3 2 2(MnO 4 +
4H + + 3e -
→MnO 2 +
2H 2 O
) 3(C 2 O 4 2 2MnO 4 +
8H + +
+
2H 2 O 2
3C 2 O 4 2 →
2
CO 3 2 +
6H 2 O
→ 2MnO 2 +
4H + + 2e -
) +
4H 2 O + 6
CO 3 2-
4
+
12H +
Separate into half reactions.
Balance each half reaction.
Add the two half reactions.
Simplify
Balancing Redox Full Reactions in Acid Solution
1.
2.
3.
4.
MnO 4 + C 2 O 4 2 → MnO 2 + CO 3 2 2(MnO 4 3(C 2 O 4 2 +
4H + + 3e -
→MnO 2 +
2H 2 O
) +
2H 2 O
→
2
CO 3 2 +
4H + + 2e -
) 2MnO 4 -
+
3C 2 O 4 2 +
2H 2 O
→ 2MnO 2
+ 6
CO 3 2 +
4H +
Separate into half reactions.
Balance each half reaction.
Add the two half reactions.
Simplify
Balancing Redox Full Reactions in Acid Solution
MnO 4 + C 2 O 4 2 → MnO 2 + CO 3 2 2(MnO 4 3(C 2 O 4 2 +
4H + + 3e -
→MnO 2 +
2H 2 O
) +
2H 2 O
→
2
CO 3 2 +
4H + + 2e -
) 2MnO 4 -
+
3C 2 O 4 2 +
2H 2 O
→ 2MnO 2
+ 6
CO 3 2 +
4H +
1.
2.
3.
4.
5.
Separate into half reactions.
Balance each half reaction.
Add the two half reactions.
Simplify Check
Balancing Redox Full Reactions in Acid Solution
MnO 4 + C 2 O 4 2 → MnO 2 + CO 3 2 2(MnO 4 +
4H + + 3e -
→MnO 2 +
2H 2 O
) 2MnO 4 3(C
+
2 O 3C 4 2 2-
-8
O 4 + 2-
2H 2 O
→ +
2H 2 O
→ 2MnO 2
2
CO 3 2 +
-8 + 6
CO 3 2-
4H
+
+ + 4H + 2e -
) 1.
2.
3.
4.
5.
Separate into half reactions.
Balance each half reaction.
Add the two half reactions.
Simplify Check
Balancing Redox Full Reactions in Basic Solution
2MnO 4 -
+
3C 2 O 4 2 +
2H 2 O
→ 2MnO 2
+ 6
CO 3 2 +
4H +
Balancing Redox Full Reactions in Basic Solution
2MnO 4 -
+
3C 2 O 4 2 +
2H 2 O
→ 2MnO 2
+ 6
CO 3 2 +
4H +
1.
Balance in acid solution
Balancing Redox Full Reactions in Basic Solution
2MnO 4 -
+
3C 2 O 4 2 +
2H 2 O
→ 2MnO 2
+ 6
CO 3 2 +
4H +
1.
2.
Balance in acid solution Add OH to neutralize the H +
Balancing Redox Full Reactions in Basic Solution
2MnO 4 -
+
3C 2 O 4 2 +
2H 2 O
→ 2MnO 2
+ 6
CO 3 2 +
4H + 4OH 4OH -
1.
2.
3.
Balance in acid solution Add OH to neutralize the H + Simplify
Balancing Redox Full Reactions in Basic Solution
2MnO 4 -
+
3C 2 O 4 2 +
2H 2 O
→ 2MnO 2
+ 6
CO 3 2 +
4H + 4OH 4OH 4H 2 O
1.
2.
3.
Balance in acid solution Add OH to neutralize the H + Simplify
Balancing Redox Full Reactions in Basic Solution
2MnO 4 -
+
3C 2 O 4 2 +
4OH -
→ 2MnO 2
+ 6
CO 3 2 +
2H 2 O
1.
2.
3.
Balance in acid solution Add OH to neutralize the H + Simplify
Balancing Redox Full Reactions in Basic Solution
2MnO 4 -
+
3C 2 O 4 2 +
4OH -
→ 2MnO 2
+ 6
CO 3 2 +
2H 2 O
1.
2.
3.
4.
Balance in acid solution Add OH to neutralize the H + Simplify Check
Balancing Redox Full Reactions in Basic Solution
2MnO 4 -
+
3C 2 O 4 2 +
4OH -
→ 2MnO 2
+ 6
CO 3 2 +
2H 2 O
1.
2.
3.
4.
Balance in acid solution Add OH to neutralize the H + Simplify Check
Balancing Redox Full Reactions in Basic Solution
2MnO 4 -
+
3C 2 O 4 2 +
4OH -
→ 2MnO 2
+ 6
CO 3 2 +
2H 2 O -12 -12
1.
2.
3.
4.
Balance in acid solution Add OH to neutralize the H + Simplify Check
Balancing Redox Full Reactions in Basic Solution
Fe + O 2 → H 2 O + Fe(OH) 2
Balancing Redox Full Reactions in Basic Solution
Fe O 2 → → Fe(OH) 2 H 2 O
Balancing Redox Full Reactions in Basic Solution
Fe + 2H 2 O → O 2 → Fe(OH) 2 H 2 O + H 2 O
Balancing Redox Full Reactions in Basic Solution
Fe + 2H 2 O → O 2 + 4H + 2H + → + H 2 O Fe(OH) 2 + H 2 O
Balancing Redox Full Reactions in Basic Solution
4e + Fe + 2H 2 O → O 2 + 4H + 2H + → + H 2 O Fe(OH) 2 + 2e + H 2 O
Balancing Redox Full Reactions in Basic Solution
4e + 2 (Fe + 2H 2 O → O 2 + 4H + 2H + → + H 2 O Fe(OH) 2 + 2e ) + H 2 O
Balancing Redox Full Reactions in Basic Solution
4e + 2 (Fe + 2H 2 O → O 2 + 4H + 2 Fe + 4H 2 O + O 2 +4 H + 2H → + + H 2 O Fe(OH) 2 + 2e ) + H 2 O → 4H + + 2Fe(OH) 2 + 2 H 2 O
Balancing Redox Full Reactions in Basic Solution
2 (Fe + 2H 2 O → 4e + 2 O 2 + 4H 2 Fe + 4H 2 O + O 2 +4 H + + 2H → + + H 2 O Fe(OH) 2 + 2e ) + H 2 O → 4H + + 2Fe(OH) 2 + 2 H 2 O
Balancing Redox Full Reactions in Basic Solution
2 (Fe + 2H 2 O → 4e + 2 O 2 + 4H + 2 Fe + 4H 2 O + O 2 + 4 H + 2H → + 2 Fe + 2H 2 O + O 2 → 2Fe(OH) 2 + H 2 O Fe(OH) 2 + 2e ) + H 2 O → 4H + + 2Fe(OH) 2 + 2H 2 O
Balancing Redox Full Reactions in Basic Solution
4e + 2 (Fe + 2H 2 O → O 2 + 4H + 2H + → + H 2 O Fe(OH) 2 + 2e ) + H 2 O 2 Fe + 2H 2 O + O 2 → 2Fe(OH) 2
No need to add OH -
As → H 2 AsO 4 + AsH 3 (alkaline)
3(As + 4H 2 O 5(3H + + As → H 2 AsO 4 + 3e → + AsH 3 ) 6H + + 5e ) 3As + 12H 2 O + 15H + + 5As → 3H 2 AsO 4 + 18H + + 5AsH 3 8As + 12H 2 O → 3H 2 AsO 4 -
3OH -
+ 3H + + 5AsH 3
3OH 3OH +
8As + 9H 2 O → 3H 2 AsO 4 + 5AsH 3
-3 -3