Sciencemadness Discussion Board

Lead(II,IV) Oxide - Minium - Pb3O4

TGWS - 26-3-2020 at 07:52

Hi,

I recently got half a kilo of Lead(II,IV) Oxide, and was wondering about what it could be used for.

I wondered if H2O2 would oxidise the Pb(II) aspect to Pb(IV), producing PbO2, which I found online was a very dark black. However, upon adding the Hydrogen Peroxide and leaving it over night in a ventilated area, it had formed pinkish crystals. What has happened here? I know PbO is a cream powder, could it be that? How would it have formed as surely that would involve reducing the Pb(IV)?

A second question, what is the best way to precipitate out dissolved Pb(II) and Pb(IV) ions, as I would like to minimise the solid waste that I produce, as lead and its compounds can't be flushed down the drain.

A third question, do you know any more simple experiments that can be done on this compound? My findings online are scarce, other than adding concentrated NaOH.

Thanks in advance! :)

Bedlasky - 26-3-2020 at 08:58

I think that H2O2 reduce Pb(IV) in to Pb(II), especially in acidic solution. If you want PbO2, try heating with persulfate or hypochlorite.

Vibzz lab have video about making PbO2. He started from lead(II) acetate, but maybe it also works with Pb3O4.

https://www.youtube.com/watch?v=0Jc1xUdvC4s

You can also make some lead(II) salts by reducing Pb3O4 in acidic solution.

TGWS - 26-3-2020 at 11:06

Hi,

Thanks for your reply, does that mean if I add Oxalic Acid, which is both acidic and a reducing agent, it should also produce Pb(II)?

Thanks! :)

Bedlasky - 26-3-2020 at 17:54

I don't know, try it in test tube scale. But you'll obtain insoluble lead oxalate.

When I once did analysis of minium in school, I dissolved it in mixture of 1+1 HNO3 and H2O2. For 1g of Pb3O4 I used 5ml of 1+1 HNO3 and 3-5ml of 35% H2O2.

Instead of HNO3 you can try it with acetic acid. But try it firstly in test tube scale.

[Edited on 27-3-2020 by Bedlasky]

RogueRose - 27-3-2020 at 01:15

Quote: Originally posted by Bedlasky  
I don't know, try it in test tube scale. But you'll obtain insoluble lead oxalate.

When I once did analysis of minium in school, I dissolved it in mixture of 1+1 HNO3 and H2O2. For 1g of Pb3O4 I used 5ml of 1+1 HNO3 and 3-5ml of 35% H2O2.

Instead of HNO3 you can try it with acetic acid. But try it firstly in test tube scale.

[Edited on 27-3-2020 by Bedlasky]


If you use acetic acid, especially with H2O2, all you are going to get is lead acetate.

yobbo II - 27-3-2020 at 17:38

http://www.sciencemadness.org/talk/viewthread.php?tid=5490