Study this chemical reaction: cr o2 -> cro2 then, write balanced half-reactions describing the oxidation and reduction that happen in this reaction.

Oxidation: Cr → Cr⁴⁺ + 4 e⁻

Reduction: 4 e⁻ + O₂ → 2 O²⁻

Explanation:

Let's consider the following redox reaction.

Cr + O₂ → CrO₂

Cr is oxidized. Its oxidation number increases from 0 to +4. The corresponding half-reaction is:

Cr → Cr⁴⁺ + 4 e⁻

O is reduced. Its oxidation number decreases from 0 to -2. The corresponding half-reaction is:

4 e⁻ + O₂ → 2 O²⁻

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