During Kolbe's electrolysis of aqueous sodium acetate (), ethane gas is produced at the anode alongs — Hydrocarbons Chemistry Question
Question
During Kolbe's electrolysis of aqueous sodium acetate ($CH_3COONa$), ethane gas is produced at the anode alongside carbon dioxide. What is the stoichiometric ratio (moles of $CO_2$ : moles of ethane) of the gases evolved strictly from the anodic oxidation of the acetate ion?
💡 Solution & Explanation
The anodic reaction for Kolbe's electrolysis of sodium acetate involves the oxidation of two acetate ions to form two methyl radicals and two molecules of $CO_2$. The two methyl radicals then couple to form one molecule of ethane ($C_2H_6$). The balanced anodic half-reaction is: $2CH_3COO^- \to C_2H_6 + 2CO_2 + 2e^-$. Thus, 2 moles of $CO_2$ are produced for every 1 mole of ethane.