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SCX Chemistry · Chapter 3: Half equations and overall redox equations

Year 11 SCX · About 17 minutes with activities · Turn your sound on

Chapter 3 · Half and overall equations
Half-equation balancerkeep the atoms and the charge level

Chapter 3 recap

  • Half equation: one half of a redox reaction, with the electrons shown. e⁻ on the right = oxidation (lost); e⁻ on the left = reduction (gained).
  • Four steps: 1 balance the main species · 2 balance O with H₂O · 3 balance H with H⁺ · 4 balance charge with e⁻ on the more positive side.
  • Overall equation: no spectator ions · multiply to the lowest common multiple of e⁻ · add · cancel e⁻, H⁺ and H₂O · check atoms and charge.
  • Next: Chapter 4 · Redox observations

Where do the H⁺, water and electrons in a redox equation come from?

Chapter 3 · About 17 minutes · sound on

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