# Why are peroxides explosive?

Why do peroxides tend to explode with little provocation? In general, what are typical products of their explosion?

• In general, molecules possessing two highly electronegative atoms that are directly bonded (in your case, the two adjacent oxygens) are rather unruly substances; the weak -O-O- bond is easily cleaved. – user95 Jul 8 '12 at 16:42
• Thanks! Would the bond tend to split homo- or heterolytically? – Nick Jul 8 '12 at 22:38
• OH radicals are fairly stable, and I can't see why charges should be separated, so a homolytical cleavage at the O-O bond sounds reasonable. – Karl Apr 10 '16 at 23:55

But we can talk, for instance, about hydrogen peroxide. One of the most familiar schemes is a disproportionation where, $$2 \ce{H2O2} \rightarrow 2\ce{H2O} + \ce{O2}$$ and as you study this particular species, you will see this reaction more and more often. Actually in solutions of hydrogen peroxide you can take a 30% concentrated solution and add some Mn and subsequently measure a significant increase in oxygen concentration over time. Although you should know the solution itself decomposes slowly in practice when exposed to light or due to trace impurities, but this pales in comparison to the case involving a catalyst. This reaction is, in part, why researchers believe a peroxide-type species is important for the Oxygen Evolving Center of Photosystem II. Another fun demonstration of this process is often where foam is generated from a large graduation cylinder, see here, upon addition of KI.