Balancing Redox Reactions Calculator

Redox reaction is a combination of oxidation and reduction. The reaction occurs when a transfer of electrons between two species takes place. The loss of electrons and increase in the oxidation state of the reactant is called oxidation. The gain of electrons and the decrease in the oxidation state of the reactant is reduction.

The different types of redox reactions are decomposition reaction, combination reaction, displacement reaction, and disproportionation reaction.

The redox reaction can be balanced in two ways i.e oxidation number method and the half-reaction method. The simple steps to balance the redox reaction with the help of the half-reaction method are listed here.

• Firstly, divide the whole chemical reaction into two half-reactions, one denotes oxidation and the other denotes reduction.
• Balance elements that are other than "O" and "H" atoms.
• In an alkaline medium, the oxygen is balanced by adding water H₂O and the same no of OH^- ions are added on the opposite side and add OH^- if required.
• In an acidic or neutral medium, balance "O" atoms by adding water H₂O and balance H^- atoms by adding H⁺ ions.
• Balance the changes on both sides by adding electrons.
• Multiply with a suitable integer at required positions.
• Add both half-reactions.

Example:

Balance the following redox reaction with the half-reaction method.

Fe²⁺ + Cr₂O₇^2- → Fe³⁺ + Cr³⁺

Solution:

Divide the equation into two separate half reaction-oxidation half and reduction half.

Oxidation half is Fe²⁺ → Fe³⁺

Reduction half is Cr₂O₇^2- → Cr³⁺

Balance the redox reaction.

Cr₂O₇^2- → 2Cr³⁺

Add water molecule

Cr₂O₇^2- + 14 H⁺ → Cr³⁺ + 7H₂O

Balance charges

Fe²⁺ → Fe³⁺ + e^-

Cr₂O₇^2- + 14 H⁺ + 6e^- → 2Cr³⁺ + 7H₂O

6Fe²⁺ → 6Fe³⁺ + 6e^-

6Fe²⁺ + Cr₂O₇^2- + 14 H⁺ → 2Cr³⁺ + 6Fe³⁺ + 7H₂O

1. Which method is easy for balancing redox reactions?

The half-reaction method is easy for balancing the redox reactions.

2. What are the rules for balancing redox reactions?

The simple rules for balancing redox reactions are here.

• Split the chemical equation into two half-reactions.
• Balance each half-reaction for mass & charge.
• Equate the number of electrons transferred in every half-reaction.
• Add half-reactions together.

3. How to use Balancing Redox Reactions Calculator with steps?

Provide the unbalanced chemical reaction in the input box of the calculator. Hit the calculate button. It will automatically display the balanced redox reaction as output.

4. Why do we use half-reactions?

Half reactions are used to balance the redox reaction. For oxidation-reduction reactions in acidic conditions, after balancing the atoms & oxidation numbers, one has to add H⁺ ions to balance the hydrogen ions in the half-reaction.