Redox reactions

These pages provide some exercises for you to practice balancing redox equations using the half-reaction method. If you choose the "with help" options, the page will walk you through the exercise and will not allow you to proceed if you make a mistake. The "without help" options allow you to try solving the exercise on your own, and only checks the final answer. You can return to this page at any moment using the link at the bottom of each page.

Some notes on balancing redox reactions using this method are available as a PowerPoint presentation, or as a pdf document.

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1. Balance half equations with help:
• Cr₂O₇^2- in acid medium.
• NO₂ in acid medium.
• Br^- in basic medium.
• MnO₄^- in basic medium.


2. Balance full equations with or without help:
• Fe²⁺/MnO₄^- in acid medium.
• With help.
• No help.
• Cl₂ in basic medium.
• With help.
• No help.


3. Balance full equations with no help:
• Cl₂ in acid medium.
• Zn²⁺/MnO₂ in basic medium.