What is the role of Cr2O7^2-/H+ in the oxidation steps described?

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Multiple Choice

What is the role of Cr2O7^2-/H+ in the oxidation steps described?

Cr2O7^2-/H+ acts as the oxidising agent in these oxidation steps. In acidic solution, dichromate is a strong electron acceptor, pulling electrons (and associated hydrogens) from the organic substrate and driving its oxidation from alcohol toward aldehyde/ketone, or further to carboxylic acid under harsher conditions. As it oxidizes the substrate, the chromium is reduced from Cr(VI) to Cr(III), so the reagent is consumed rather than regenerated. That’s why it’s not a catalyst. It’s also not a solvent; its role is to oxidize the substrate by accepting electrons, which is the hallmark of an oxidising agent. A representative half-reaction shows the chromium oxyanion accepting electrons to form Cr3+ and water.

Cr2O7^2-/H+ acts as the oxidising agent in these oxidation steps. In acidic solution, dichromate is a strong electron acceptor, pulling electrons (and associated hydrogens) from the organic substrate and driving its oxidation from alcohol toward aldehyde/ketone, or further to carboxylic acid under harsher conditions. As it oxidizes the substrate, the chromium is reduced from Cr(VI) to Cr(III), so the reagent is consumed rather than regenerated. That’s why it’s not a catalyst. It’s also not a solvent; its role is to oxidize the substrate by accepting electrons, which is the hallmark of an oxidising agent. A representative half-reaction shows the chromium oxyanion accepting electrons to form Cr3+ and water.

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