Combining Half-Equations

Part of the Oxidation and Reduction section of Coddy's Chemistry journey. Lesson 14 of 27.

Multiply each half-equation so the electrons match.

MnO₄⁻ takes 5e⁻; each Fe²⁺ gives 1e⁻, so take 5 Fe²⁺.

Add and cancel the electrons:

MnO₄⁻ + 8H⁺ + 5Fe²⁺ → Mn²⁺ + 5Fe³⁺ + 4H₂O

Challenge

Permanganate is used to measure iron(II) in iron tablets: MnO₄⁻ + H⁺ + Fe²⁺ → Mn²⁺ + Fe³⁺ + H₂O. Balance the full equation.

Try it yourself

Equation balancerBalance the equation

MnO₄⁻H⁺Fe²⁺Mn²⁺Fe³⁺H₂O

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Oxidation and Reduction

1Electron Transfer

4Metals and Reactivity

2Redox Reactions

5Electrochemistry

3Half-Equations

6Practice Problems