Action of Oxidising Agents

Quinone is produced in small yield by direct oxidation of benzene itself with silver peroxide, but better by the action of oxidising agents on a large number of its p-disubstitution products. Thus, in addition to quinol, p-aminophenol (experiment, p. 176), p-anisidine, p-toluidine, and sulphanilic acid as well as p-phenylenediamine and many of its derivatives yield quinone in this way. 

This metal is found associated with iridium, constituting a small part of the ore of platinum, which is insoluble in aqua regia. When this residue is acted on at a red-heat, by nitre, both the metals are oxidised, and the mass being distilled with sulphuric acid, yields osmic acid. Os 0, which condenses in fusible crystals. From the acid, the metal may be obtained by the action of reducing agents, as a black powder, which becomes metallic by friction. 

The use of potentiostatic curves has also facilitated the study of the rdle of oxidising agents and inhibitors in corrosion processes. Sterndiscussed the rdle of passivating-type inhibitors and used potentiostatic curves to explain their action. Poseyused the potentiostatic technique for determining the reduction of cupric ion on stainless steel. Both of these references... 

Silver in the +3 oxidation state, including silver peroxide, ie, black oxide, marketed as AgO, is obtained by the action of the vigorous oxidising agent S20 g on Ag20 or other Ag compounds. X-ray and neutron diffraction analyses show the nominal AgO unit cell to be Ag20 Ag202- Both Ag" and Ag " are present. Another compound of potentially important commercial value is Ag O, which has a unit cell of two Ag and two Ag ions. Its preparation is as follows ... 

Action of chlorine trifluoride causes incandescence [1]. Manganese dioxide catalytically decomposes powerful oxidising agents, often violently. Dropped into cone, hydrogen peroxide, the powdered oxide may cause explosion [2], Either the massive or the powdered oxide explosively decomposes 92% peroxomonosulfuric acid [3], and mixtures with chlorates ( oxygen mixture , heated to generate the gas) may react with explosive violence [4], Cuban pyrolusite can be used in place of potassium dichromate to promote thermal decomposition of potassium chlorate in match-head formulations [5],... 

Measured quantities of the pre-ferment are mixed with flour. The dough is then subjected to the combination of intense mixing and the action of the oxidising agent. It is then extruded and cut into loaf sized portions, proved and baked. Bread made by the Do-Maker process has a very even crumb texture, which is characteristic of the process. 

Polyethylene remains unaffected an action with most acids, alkalis and aqueous solution. Strong oxidising agents like nitric acid and hydrogen peroxide, etc. cause deterioration, deterioration also take place with oxygen in presence of ultraviolet light hence antioxidants are added to the polymer. Polyethylene may be cross-linked by exposure to X-rays, Y-rays, fast electrons or by treatment with peroxides. 

The sweetening agent saccharin is also derived from a sulphonamide it is prepared from toluene-o-sulphonamide by oxidising the CHs-group to carboxyl with permanganate ring closure is subsequently brought about by the action of concentrated hydrochloric acid ... 

By the oxidation of a large number of organic compounds. Most organic substances are converted by oxidising agents into oxalic acid before their final transformation into carbonic anbydride and water thus sugar is transformed into oxalio acid by the action of nitric acid. 

Most oxidising agents affect sulphur, the vigour of the action varying with the conditions and with the nature of the agent. A mixture of sulphur and potassium chlorate is highly explosive and will detonate violently on slight shock. Nitric acid oxidises sulphur quantitatively to sulphuric acid. When heated with sulphur, most metallic oxides are converted into sulphide and sulphate mercury, lead, bismuth and cadmium oxides are common examples 5... 

That sulphur dioxide can function either as an oxidising agent or as a reducing agent, according to the conditions, has been shown in the case of certain chlorides, sulphates and phosphates.7 The concentration of acid which is added is an important factor, for, by varying the amount present, the sulphur dioxide can be made either to oxidise or to reduce. The action of sulphur dioxide on the chlorides of mercury illustrates this diversity of action. Quantitative results are produced only under very specific conditions. A solution of mercuric chloride (1 80) saturated with sulphur dioxide at 70° to 80° C. and kept at... 

Mercuric thiocyanate, which is formed as a white precipitate when mercuric nitrate and potassium thiocyanate solutions are mixed, is soluble in excess of either solution. When dried, this salt is inflammable, forming a voluminous ash known as Pharaoh s serpents. By the interaction of a mercuric salt with ammonium thiocyanate and thio-carbamide in acetic acid solution in the presence of an oxidising agent, or by the action of hydrogen sulphide on mercuric thiocyanate, the phototropic compound HS.Hg.CNS is obtained.6... 

Colorimetric Methods are used only for the estimation of very small percentages of vanadium, e.g. in vanadium steels and alloys. The most important depend on the intensity of the reddish-brown colour produced by the action of hydrogen peroxide on an acid vanadate solution.3 If chromium is present, an equal amount must be introduced into the standard vanadium solution under the same conditions of temperature, acid concentration, etc. Phosphoric acid is added to destroy any yellow colour due to ferric iron, and either hydrofluoric acid or ammonium fluoride to destroy any colour produced by titanium.4 A colorimetric method for the simultaneous estimation of small quantities of titanium and vanadium has also been worked out.5 Other colorimetric processes are based on (a) the formation of a yellow to black coloration, due to aniline black, in the presence of aniline hydrochloride and potassium chlorate or other oxidising agent,6 and (b) the orange coloration finally produced when an acid solution of a vanadate is brought into contact with strychnine sulphate.7... 

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