My textbook says lead reacts with acetic acid when there is enough oxygen to oxidize lead:

$$\ce{2 Pb + O2 + 4 CH3COOH -> 2 Pb(CH3COO)2 + 2 H2O}$$

So, I added lead into mixed solution of acetic acid and hydrogen peroxide. Immediately bubbles began to emit from the surface of the lead piece. After several days the lead chunk has been completely dissolved and pale yellow precipitate was formed. This is not what I expect considering the reaction above. Can the bubbling be attributed to the oxidation of lead by water?

I used rice vinegar as a source of acetic acid. It might have been contaminated with ions like $\ce{Cl-}$.

  • 1
    $\begingroup$ You quote the reaction of lead with oxygen as oxidant, but you used hydrogen peroxide as oxidant. The two conditions give different outcomes. $\endgroup$
    – Waylander
    Oct 5, 2022 at 6:41
  • 2
    $\begingroup$ This reaction most likely needs to be run in neat acetic acid to give the outcome you want. Rice vinegar is mostly water. $\endgroup$
    – Waylander
    Oct 5, 2022 at 7:35
  • $\begingroup$ As lead can exist in more oxidation states, it may catalyze the parallel reaction of hydrogen peroxide decomposition to water and oxygen. $\endgroup$
    – Poutnik
    Oct 5, 2022 at 7:51
  • $\begingroup$ @Poutnik It seems you are right. I tried this experiment without vinegar this time and bubbles were emitted too. So, it is highly probable that lead acts as a catalyst. $\endgroup$ Oct 5, 2022 at 10:58
  • $\begingroup$ You must check the composition of the bubbles. Lead will react in acid to give H2 and in the acidic solution the lead did react so there are possibly several concurrent reactions: reaction of lead with acid and water to give hydrogen, oxidation of lead by peroxide to give lead ion and water, decomposition of peroxide to give O2, in acid possible oxidation of Pb++ to PbO2 [barely possible but since nothing is controlled here who knows]. You might try just lead and acid while you are at it. Get some distilled white vinegar, almost pure acetic acid in water. Why are you interested in lead acetate $\endgroup$
    – jimchmst
    Oct 6, 2022 at 0:31


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