Final answer:
The balanced equation for the reaction of ethanol with potassium dichromate in acid to produce ethanoic acid and Cr³⁺ is 3 C₂H₅OH + 2 K₂Cr₂O₇ + 8 H₂SO₄ → 2 Cr₂(SO₄)₃ + 3 CH₃COOH + 2 K₂SO₄ + 11 H₂O.
Step-by-step explanation:
The balanced chemical equation for the reaction between ethanol (C₂H₅OH) and potassium dichromate (K₂Cr₂O₇) in acidic conditions to produce ethanoic acid (CH₃COOH) and Cr³⁺ ions is:
3 C₂H₅OH + 2 K₂Cr₂O₇ + 8 H₂SO₄ → 2 Cr₂(SO₄)₃ + 3 CH₃COOH + 2 K₂SO₄ + 11 H₂O.
This reaction occurs in the presence of dilute sulfuric acid, where ethanol is oxidized to ethanoic acid, and in the process, the chromium (VI) in potassium dichromate is reduced to chromium (III).
The change in color from yellow-orange to green upon reduction provides visual evidence of the reaction taking place, and this principle is used in breathalyzers to estimate blood alcohol content.