Hydrogen peroxide (WAS: ... Major incompatibilities)

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From:"J. A. Kiernan" <jkiernan@julian.uwo.ca>
To:Histonet <histonet@pathology.swmed.edu>
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On Thu, 4 May 2000, George King wrote:

>                        ...  The mixing of acetone and any strong
> oxidising agent (including hydrogen peroxide) is to be avoided, this is
> listed in an old BDH handbook which I have as one of the major
> incompatibilities likely to cause violent reactions.

  This warning applies to strong solutions of hydrogen peroxide,
  such as 30% (= 100 vols available O2). When making a solution in
  acetone or (more usually) methanol the strong stuff is diluted
  first with water, and nothing untoward happens. 

  It's often not appreciated (though it's in even the most elementary
  chemistry textbooks) that hydrogen peroxide is also a reducing agent.
  For example, it is oxidized by permanganate, with liberation of
  oxygen. It can also oxidize and reduce itself. Two molecules of
  H2O2 react to make two waters and one O2. This reaction, which occurs
  when hydrogen peroxide deteriorates and changes into water, is
  catalyzed by many substances, including phosphate ions and metals
  (elemental or ionic). If you pour hair bleaching strength H2O2
  (5% or 10%) onto som iron filings you'll see a brisk effervescence 
  of oxygen and will recover your iron filings unchanged (if you dry
  them afterwards to prevent ordinary rusting).

 John A. Kiernan,
 Department of Anatomy & Cell Biology,
 The University of Western Ontario,
 LONDON,  Canada  N6A 5C1

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