Do you have a redox equation you don't know how to balance? Besides simply balancing the equation in question, these programs will also give you a detailed overview of the entire balancing process with your chosen method.

1. Ion-electron method (also called the half-reaction method)
2. Oxidation number change method
3. Aggregate redox species method (or ARS method) - New on periodni.com [1]

BALANCING REDOX REACTIONS

In the ion-electron method (also called the half-reaction method), the redox equation is separated into two half-equations - one for oxidation and one for reduction. Each of these half-reactions is balanced separately and then combined to give the balanced redox equation.

Enter an equation of a chemical reaction and click 'Submit' (for example: mn2++bio3-+h+=mno4-+bi3+ ).

Rules for typing equations

• Spaces are irrelevant, for example Cu SO 4 is equal CuSO4
• All types of parentheses are correct, for example K3[Fe(CN)6]
• To enter charge species, just type them as they are, for example Hg2+, Hg22+, or Hg2^2+
• To enter the equation sign, you can use either "=" or "-->" or "→" symbols.
• The equation can be written in lowercase letters. If the elements in a chemical formula are properly capitalized, the smart case converter leaves them as you have typed.

Why must chemical equations be balanced?

A balanced chemical equation accurately describes the quantities of reactants and products in chemical reactions. The Law of Conservation of Mass states that mass is neither created nor destroyed in an ordinary chemical reaction. This means that a chemical equation must have the same number of atoms of each element on both side of the equation. Also the sum of the charges on one side of the equation must be equal to the sum of the charges on the other side. When these two conditions are met, the equation is said to be balanced.

Guidelines for balancing redox equations

• Step 1. Write down the unbalanced equation
• Step 2. Separate the redox reaction into half-reactions
  • a) Assign oxidation numbers for each atom
  • b) Identify and write out all redox couples in reaction
  • c) Combine these redox couples into two half-reactions
• Step 3. Balance the atoms in each half reaction
  • a) Balance all other atoms except H and O
  • b) Balance the oxygen atoms with H₂O
  • c) Balance the hydrogen atoms with H⁺
  • d) In a basic medium, add one OH^- to each side for every H⁺
• Step 4. Balance the charge with e^-
• Step 5: Make electron gain equivalent to electron loss in the half-reactions
• Step 6: Add the half-reactions together
• Step 7: Simplify the equation
• Finally, check that the elements and charges are balanced

Sample redox equations

Ionic vs molecular equation form

When an equation is written in the molecular form the program will have issues balancing atoms in the half-reactions (Step 3.). This is avoided by writing the equation in the ionic form.

Different solutions