Consider the following pairs of reactions and properties: Reactions / Properties I. Fe(s) + 2HCl(aq) → FeCl₂(aq) + H₂(g) / Fe is reductant II. Zn(s) + CuSO₄(aq) → ZnSO₄(aq) + Cu(s) / Cu is being reduced III. Br₂(l) + 2I⁻(aq) → 2Br⁻(aq) + I₂(s) / Br₂ is reductant IV. CH₄(g) + 2O₂(g) → CO₂(g) + 2H₂O(l) / C atom in CH₄ is oxidized Which of the above pairs are correct?
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