Which equation best represents the oxidation half-equation that occurs when iron rusts?

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Question

Which equation best represents the oxidation half-equation that occurs when iron rusts?

Accepted Answer

Fe → Fe²⁺ + 2e⁻ — Award 1 mark for recognizing that iron atoms lose electrons (are oxidized) during rusting. A is incorrect because it shows reduction (gain of electrons), not oxidation. C is incorrect because it also shows reduction. D is incorrect because it shows the reduction half-equation for oxygen, not the oxidation of iron.

Answer

Fe → Fe²⁺ + 2e⁻

Answer

Fe²⁺ + 2e⁻ → Fe

Answer

O₂ + 4e⁻ + 2H₂O → 4OH⁻

Answer

Fe³⁺ + 3e⁻ → Fe

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