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The main finding of Haber and Weiss was that hydrogen peroxide (H 2 O 2) is decomposed by a chain reaction. [2] The Haber–Weiss reaction chain proceeds by successive steps: (i) initiation, (ii) propagation and (iii) termination. The chain is initiated by the Fenton reaction: Fe 2+ + H 2 O 2 → Fe 3+ + HO – + HO • (step 1: initiation)
Hydrogen peroxide is a chemical compound with the formula H 2 O 2.In its pure form, it is a very pale blue [5] liquid that is slightly more viscous than water.It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%–6% by weight) in water for consumer use and in higher concentrations for industrial use.
As hydrogen peroxide enters the active site, it does not interact with the amino acids Asn148 (asparagine at position 148) and His75, causing a proton (hydrogen ion) to transfer between the oxygen atoms. The free oxygen atom coordinates, freeing the newly formed water molecule and Fe(IV)=O.
In the first step of the catalytic cycle, H 2 O 2, or an organic peroxide, enters the active site of MnP. There the oxygen in H 2 O 2 binds to an Fe(III) ion in the heme cofactor to form an iron peroxide complex. Two electrons are transferred from Fe 3+ to peroxide, breaking the oxygen-peroxide bond to form H 2 O and a Fe(IV) oxo-porphyrin ...
Fenton's reagent is a solution of hydrogen peroxide (H 2 O 2) and an iron catalyst (typically iron(II) sulfate, FeSO 4). [1] It is used to oxidize contaminants or waste water as part of an advanced oxidation process.
3), the anion of iodic acid, in the catalytic conversion of hydrogen peroxide to oxygen and water by the iodate. He observed that the concentration of iodine molecules oscillated periodically and that hydrogen peroxide was consumed during the reaction. An increase in temperature reduces the cycle in the range of hours.
Hydrogen peroxide is not nearly as reactive as these species, but is readily activated and is thus included. [3] Peroxynitrite and nitric oxide are reactive oxygen-containing species as well. Hydroxyl radical ( HO· ) is generated by Fenton reaction of hydrogen peroxide with ferrous compounds and related reducing agents:
The initial aqueous solution contains hydrogen peroxide, an iodate, divalent manganese (Mn 2+) as catalyst, a strong chemically unreactive acid (sulphuric acid (H 2 SO 4) or perchloric acid (HClO 4) are good), and an organic compound with an active ("enolic") hydrogen atom attached to carbon which will slowly reduce free iodine (I 2) to iodide (I −).