Redox Reaction Balancer
Balance redox reactions step by step using the half-reaction method in acidic, basic, or neutral solution. See oxidation numbers, electron transfer, and a clear sequence of balancing steps.
No Redox Results Yet
Enter an unbalanced redox reaction and choose whether the solution is acidic, basic, or neutral. This tool will try to show oxidation numbers, split the reaction into half-reactions, and walk you through a textbook-style balancing sequence.
Example reactions:
- Fe2+ + Cr2O7^2- → Fe3+ + Cr3+
- MnO4- + Fe2+ → Mn2+ + Fe3+
- Zn + Cu2+ → Zn2+ + Cu
Understanding Redox Reactions
Learn about oxidation-reduction reactions and the half-reaction method for balancing them in aqueous solutions.
What is a Redox Reaction?
A redox reaction (reduction-oxidation) involves the transfer of electrons between chemical species. One species loses electrons (oxidation) while another gains electrons (reduction).
Remember: OIL RIG
- Oxidation Is Loss (of electrons)
- Reduction Is Gain (of electrons)
Oxidation Numbers
Oxidation numbers (or oxidation states) help track electron transfer. They follow simple rules:
- • Free elements (e.g., Zn, Cl₂) have oxidation state 0
- • Monatomic ions equal their charge (Na⁺ = +1)
- • Hydrogen is usually +1
- • Oxygen is usually −2
- • Sum of oxidation states = net charge of species
The Half-Reaction Method
1. Identify half-reactions
Separate oxidation and reduction processes
2. Balance atoms (except O and H)
Adjust coefficients for the main elements
3. Balance O with H₂O
Add water molecules to balance oxygen
4. Balance H with H⁺ (or OH⁻)
Use H⁺ in acidic, convert to OH⁻ in basic
5. Balance charge with e⁻
Add electrons to equalize charge
6. Combine and simplify
Multiply to equalize electrons, add, and cancel
Acidic vs Basic Solutions
Acidic Solution
Use H⁺ and H₂O directly. Common in most titrations and lab reactions.
Basic Solution
First balance as acidic, then add OH⁻ to both sides to neutralize H⁺ and form H₂O.
Educational Disclaimer: This tool uses simplified oxidation-state rules designed for textbook-style examples. Complex coordination chemistry, multi-step mechanisms, and exotic species may not be handled accurately. For learning and homework practice only—not for lab procedures or industrial applications.
Frequently Asked Questions
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