Australia's Science Forum

I just tried this and it worked - even with 3% peroxide

https://www.youtube.com/watch?v=-LbMkp5DWHA

It's magic. Just tried it out on my dropper bottles. Pour in, swirl and pour back into the beaker for the next bottle. Then rinse and leave on drying rack. Thank you for the information.

Worked!! that was too easy. thanks for sharing.

Also Oxalic acid works well.

Hi Everyone,
dilute Solution (concentration does not matter - approx. 0.1 M will be sufficient)
of Iron (II) ammonium sulfate will help to remove any stain of KMnO4.

I have been using it for long time without any problem to clean the burettes stained with KMnO4 after titration.

The used solution can be stored back and used again next time for cleaning...

I hope it assists..

Nehal Trivedi

Just buy SO2 Sterilizer in Woolies home brew section. It is Sodium Metabisulphite and can not be beaten for this application.

Even safer and just as effective - a vitamin c tablet or powder dissolved in a small amount of water and poured on to the stain will do the job with no stress ,toxic solutions or SO2 to breathe. (ascorbic acid is an excellent reducing agent).
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