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Hydrogen peroxide, acidic

The product is a solid yellow hydrated oxide. If prepared by a method in the absence of water, a black anhydrous product is obtained. Germanium(II) oxide is stable in air at room temperature but is readily oxidised when heated in air or when treated at room temperature with, for example, nitric acid, hydrogen peroxide, or potassium manganate(VII). When heated in the absence of air it disproportionates at 800 K ... [Pg.191]

Addition of an oxidising agent to a solution of an iodide (for example concentrated sulphuric acid, hydrogen peroxide, potassium dichromate) yields iodine the iodine can be recognised by extracting the solution with carbon tetrachloride which gives a purple solution of iodine. [Pg.349]

Quantum, by contrast, converted an ethylene—carbon monoxide polymer into a polyester-containing terpolymer by treatment with acidic hydrogen peroxide, the Baeyer-Villiger reaction (eq. 11). Depending on the degree of conversion to polyester, the polymer is totally or partially degraded by a biological mechanism. [Pg.476]

The most important of these is the diboride, TiB2, which has a hexagonal stmeture and lattice parameters of a = 302.8 pm and c = 322.8 pm. Titanium diboride is a gray crystalline soUd. It is not attacked by cold concentrated hydrochloric or sulfuric acids, but dissolves slowly at boiling temperatures. It dissolves mote readily in nitric acid/hydrogen peroxide or nitric acid/sulfuric acid mixtures. It also decomposes upon fusion with alkaU hydroxides, carbonates, or bisulfates. [Pg.117]

Again, as with pyridopyrimidines, the main reaction is oxidation of di- or poly-hydro derivatives to fully aromatic structures, often merely by air or oxygen. In some cases the reagent of choice is mercury(II) oxide, whilst other reagents used include sulfur, bromine, chloranil, chromium trioxide-acetic acid, hydrogen peroxide, and potassium ferricyanide, which also caused oxidative removal of a benzyl group in the transformation (306) (307)... [Pg.237]

Surprisingly, there are very few examples of successful fV-oxidation of pyrazoles. Simple fV-alkylpyrazoles generally do not react with peracids (B-76MI40402,77JCS(P1)672). The only two positive results are the peracetic acid (hydrogen peroxide in acetic acid) transformation of 1-methylpyrazoIe into 1-methylpyrazole 2-oxide (268) in moderate yield and the peroxy-trifluoroacetic acid (90% hydrogen peroxide in trifluoroacetic acid) transformation of 5-amino-l-methylpyrazoIe into l-methyl-5-nitropyrazoIe 2-oxide (269). [Pg.234]

Mercury, chlorine, calcium hypochlorite, iodine, bromine or hydrogen fluoride Acids, metal powders, flammable liquids, chlorates, nitrites, sulphur, finely-divided organics or combustibles Nitric acid, hydrogen peroxide... [Pg.233]

Other oxidizing agents that can be used include nitric acid, hydrogen peroxide, peroxydisulfate, chlorate and the pervanadyl ion. The anhydrous... [Pg.432]

To limit the total porosity of the coating, checking by the Iron Solution Value (ISV) test in which samples are immersed under standard conditions in a solution of sulphuric acid, hydrogen peroxide and ammonium thiocyanate, and the amount of iron dissolved is measured... [Pg.506]

In this context, the esterification of 4-(l-pyrenyl)butyric acid with an alcohol to the corresponding ester was investigated [171]. Without the presence of sulfuric acid no reaction to the ester was foimd in the micro reactor. On activating the surface by a sulfuric acid/hydrogen peroxide mixture, however, a yield of 9% was achieved after 40 min at 50 °C. On making the surface hydrophobic by exposure to octadecyltrichlorosilane, no product formation was observed. Using silica gel in a laboratory-scale batch experiment resulted in conversion, but substantially lower than in the case of the micro reactor. The yield was no higher than 15% (40 min ... [Pg.75]

P 21] Solutions of 10 M 4-(l-pyrenyl)butyric acid in ethanol and 10 M sulfuric acid in ethanol were contacted in a micro-mixing tee/micro channel flow configuration at room temperature and at 50 °C [91]. Pressure-driven feed was used. The glass surface of the micro channels was either tuned hydrophobic (by exposure to octadecyltrichlorosilane) or hydrophilic (by wetting with a sulfuric acid/hydrogen peroxide mixture). [Pg.715]

Oxidation Is usually brought about by using the acetic acid/hydrogen peroxide mixture (the acHve species is peracetic acid). Ozonide is highly dangerous, especially when it is insoluble in the medium. [Pg.242]

Benzaldehyde was oxidised by the action of a formic acid/hydrogen peroxide mixture on this compound. There was an extremely violent reaction. The reaction has to be carried out by adding the peroxide very slowly onto the benzaldehyde/formic acid mixture to aliow the performic acid to react with benzaldehyde as it forms. A similar accident was observed when replacing benzaldehyde with formol. [Pg.309]

The effect of the nitric acid/hydrogen peroxide mixture on acetone when it is hot gives rise to an explosive oxidation, especially when the medium is confined. This situation also applies to a large number of ketones, and in particular, cyclic ketones. Cyclic di- and triperoxides form compounds that detonate, if there is no strict and very delicate thermal control. Accidents have been reported with butanone, 3-pentanone, cyclopentanone, cyclohexanone and methylcyclo-hexanones. [Pg.309]

Acetone was accidentally introduced into a reactor containing a sulphuric acid/nitric acid/hydrogen peroxide mixture. This led to an explosion due to acetone oxidation by the peroxymonosulphuric acid formed by the oxidising mixture. [Pg.309]

Note that in these three examples involving hydrogen peroxide, chromium trioxide and sodium nitrite, dangerous reactions have been described for carboxyiic acids (see on p.316-317). They all referred to the three following systems acetic acid-/hydrogen peroxide, acetic acid/chromium trioxide and o-phthalic acid/sodium nitrite. One can ask oneself whether the same reactions did not take place after the acetic and phthalic anhydride hydrolysis. [Pg.331]

The treatment of thiourea using a nitric acid/hydrogen peroxide mixture is used to make a thiourea peroxide, which decomposes explosively by giving rise to a mixture of sulphur and sulphur dioxide, when attempting to carry out air drying. [Pg.346]

Aniline Bromine Nitric acid, hydrogen peroxide Ammonia, acetylene, butadiene, butane or other petroleum gases, sodium carbide, turpentine, benzene, or finely-divided metals... [Pg.165]

Pyridine-N-oxide has been prepared by oxidation of pyridine with perbenzoic acid,4 with monoperphthalic acid,6 with peracetic acid (hydrogen peroxide and acetic acid),6-7 and with hydrogen peroxide and other carboxylic acids.7... [Pg.101]

Oxidants more concentrated than air are of greater hazard potxential, and the extent of involvement of the common oxidants Perchloric acid Chlorine Nitric acid Hydrogen peroxide Sulfuric acid METAL CHLORATES... [Pg.4]

See Bromine pentafhioride Hydrogen-containing materials Chromium trioxide Acetic acid Hydrogen peroxide Acetic acid Potassium permanganate Acetic acid Sodium peroxide Acetic acid... [Pg.319]

Among other solid P-N compounds examined, the title compound ignited immediately on contact with nitric acid, hydrogen peroxide or dinitrogen trioxide. [Pg.847]

See Nitric acid Hydrogen peroxide, Soils Nitric acid, Thiourea... [Pg.1637]

The oxidation of sulfides to the corresponding sulfoxides and sulfones proceeds under rather strenuous conditions requiring strong oxidants such as nitric acid, hydrogen peroxide, chromic acid, peracids, and periodate. Using MW irradiation, this oxidation is achievable under solvent-free conditions and with desired selectivity to either sulfoxides or sulfones using 10% sodium periodate on silica (Scheme 6.34)... [Pg.199]

Glucose + Oxygen-----——> Gluconic acid + Hydrogen peroxide (1)... [Pg.81]

Diamino-1,2,4-thiadiazoles 66, also known as Hector s bases, are the oxidation products from iV-arylthioureas 65 a large number of examples of this type of reaction are known. Typical oxidants that give good yields are acidic hydrogen peroxide, nitrous acid, and iron(m) chloride (Equation 20) <1996CHEC-II(4)307>. [Pg.501]

As mentioned earlier, reversed micelles have different properties from normal micelles. These properties have the potential to favorably affect the sensitivity and other analytical aspects of CL reactions. Thus, reversed micelles have been used to prolong the duration of the observed CL of various oxalate ester (or acid)-hydrogen peroxide-sensitizer reaction systems for application as chemical light sources [62],... [Pg.306]

Two methods were examined for digestion of biological samples prior to trace element analysis. In the first one a nitric acid-hydrogen peroxide-hydrofluoric acid mixture was used in an open system, and in the second one nitric acid in a closed Teflon bomb. The latter method was superior for Ge determination, however, germanium was lost whenever hydrogen fluoride had to be added for disolving sihcious material. End analysis by ICP-AES was used for Ge concentrations in the Xg/g range13. [Pg.344]


See other pages where Hydrogen peroxide, acidic is mentioned: [Pg.21]    [Pg.472]    [Pg.476]    [Pg.132]    [Pg.146]    [Pg.186]    [Pg.1031]    [Pg.27]    [Pg.272]    [Pg.154]    [Pg.817]    [Pg.54]    [Pg.158]    [Pg.486]    [Pg.360]    [Pg.176]    [Pg.1629]    [Pg.495]    [Pg.281]    [Pg.133]   
See also in sourсe #XX -- [ Pg.100 ]




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Carboxylic acids reactions with hydrogen peroxide

Carboxylic acids with hydrogen peroxide

Fatty acids hydrogen peroxide formation

Hydrobromic acid reaction with hydrogen peroxide

Hydrogen abstraction amino acids with peroxidized

Hydrogen peroxide Azelaic acid

Hydrogen peroxide accumulation sulfuric acids

Hydrogen peroxide acid/base properties

Hydrogen peroxide acids

Hydrogen peroxide acids

Hydrogen peroxide peracetic acid determination

Hydrogen peroxide, acid dissociation constant

Hydrogen peroxide, and formic acid

Hydrogen peroxide, and formic acid with indene

Hydrogen peroxide, fatty acid

Hydrogen peroxide, fatty acid oxidation

Hydrogen peroxide, lactic acid bacteria

Hydrogen peroxide, lactic acid bacteria production

Hydrogen peroxide, nitric acid, catalytic

Hydrogen peroxide-Acetic acid

Hydrogen peroxide-Benzeneseleninic acid

Hydrogen peroxide-Formic acid

Hydrogen peroxide-Hydrochloric acid

Hydrogen peroxide-Trichloroacetic acid

Hydrogen peroxide-Tungstic acid

Hydrogen peroxide-ascorbic acid redox

Hydrogen peroxide-ascorbic acid redox initiator

In acidic hydrogen peroxide

Iodination hydrogen peroxide, acidic

Molybdic acid, hydrogen peroxide

Nitrous acid in the presence of hydrogen peroxide

Perbenzoic acid (benzoyl hydrogen peroxide)

Phosphomolybdic acid/hydrogen peroxide

Pyridine, 2,6-dibromooxidation hydrogen peroxide in trifluoroacetic acid

Pyruvic acid, hydrogen peroxide

Uric acid hydrogen peroxide determination

With Acylating Agents Followed by Acids, Bases, or Hydrogen Peroxide (for Pyrimidin-4-ones)

With Hydrogen Peroxide or 3-Chloroperbenzoic Acid

With hydrogen peroxide in acetic acid

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