How do you balance this redox reaction using the oxidation number method? Fe2+(aq) + MnO4–(aq) --> Fe3+(aq) + Mn2+(aq)
1 Answer
WARNING: This is a long answer. The balanced equation is
Explanation:
You follow a series of steps in order:
- Identify the oxidation number of every atom.
- Determine the change in oxidation number for each atom that changes.
- Make the total increase in oxidation number equal to the total decrease in oxidation number.
- Place these numbers as coefficients in front of the formulas containing those atoms.
- Balance all remaining atoms other than
#"O"# and#"H"# . - Balance
#"O"# . - Balance
#"H"# . - Check that atoms and charges balance.
Here's how it works. Your unbalanced equation is
1. Identify the oxidation number of every atom.
Left hand side:
Right hand side:
2. Determine the change in oxidation number for each atom that changes.
3. Make the total increase in oxidation number equal to the total decrease in oxidation number.
We need 5 atoms of
4. Place these numbers as coefficients in front of the formulas containing those atoms.
5. Balance all remaining atoms other than
Done.
6. Balance
Add enough
We have 4
7. Balance
Add enough
We have 8
8. Check that atoms and charges balance.
On the left: :
On the right:
On the left:
On the right:
The balanced equation is
