Acids perchloric acid

Perchloric acid, Perchloric acid, Perchloric acid,... 

Dichlorine h ptoxide, CljO, is the most stable of the chlorine oxides. It is a yellow oil at room temperature, b.p. 353 K, which will explode on heating or when subjected to shock. It is the anhydride of chloric(VlI) acid (perchloric acid) from which it is prepared by dehydration using phosphorus(V) oxide, the acid being slowly reformed when water is added. 

Ketones Aldehydes, nitric acid, perchloric acid... 

Acid mixtures containing nitric acid and a strong acid, eg, sulfuric acid, perchloric acid, selenic acid, hydrofluoric acid, boron trifluoride, or an ion-exchange resin containing sulfonic acid groups, can be used as the nitrating feedstock for ionic nitrations. These strong acids are catalysts that result in the formation of nitronium ions, NO" 2- Sulfuric acid is almost always used industrially since it is both effective and relatively inexpensive. 

Strong oxidizing agents, such as nitric acid, perchloric acid, or ozone may cause aniline to oxidize spontaneously. Hexachloromelamine [2428-04-8] and trichioromelamine [12379-38-3] react violentiy with aniline, and in confined conditions the mixtures will explore or catch fire. 

Several common acid treatments for sample decomposition include the use of concentrated nitric acid, aqua regia, nitric—sulfuric acids, and nitric perchloric acids. Perchloric acid is an effective oxidant, but its use is ha2ardous and requkes great care. Addition of potassium chlorate with nitric acid also assists in dissolving any carbonaceous matter. 

Perchloric acid is a weU-known acetylation catalyst, especially in the fibrous method of preparing cellulose triacetate. Unlike sulfuric acid, perchloric acid does not combine with cellulose (78), ie, it does not form esters, and therefore virtually complete acetylation (DS 3.0, 44.8% acetyl) occurs. However, the extremely corrosive nature of perchloric acid and explosive nature of its salts have precluded its use industrially as an acetylation catalyst. 

However, this method is appHed only when esterification cannot be effected by the usual acid—alcohol reaction because of the higher cost of the anhydrides. The production of cellulose acetate (see Fibers, cellulose esters), phenyl acetate (used in acetaminophen production), and aspirin (acetylsahcyhc acid) (see Salicylic acid) are examples of the large-scale use of acetic anhydride. The speed of acylation is greatiy increased by the use of catalysts (68) such as sulfuric acid, perchloric acid, trifluoroacetic acid, phosphoms pentoxide, 2inc chloride, ferric chloride, sodium acetate, and tertiary amines, eg, 4-dimethylaminopyridine. 

Reagents such as water, ammonia, hydrochloric acid, nitric acid, perchloric acid, and sulfuric acid can be purified via distillation (preferably under reduced pressure and particularly with perchloric acid) using an allglass still. Isothermal distillation is convenient for ammonia a beaker containing concentrated ammonia is placed alongside a beaker of distilled water for several days in an empty desiccator so that some of the ammonia distils over into the water. The redistilled ammonia should be kept in polyethylene or parafrin-waxed bottles. Hydrochloric acid can be purified in the same way. To ensure the absence of metal contaminants from some salts (e.g. ammonium acetate), it may be more expedient to synthesise the salts using distilled components rather than to attempt to purify the salts themselves. 

Nitrohydrochloric acid Perchloric acid Phenosulphonic acid Phosphorus pentoxide Propionic acid Selenic acid Spent acids Sulphamic acid Sulphuric acid and oleum (fuming sulphuric acid) Sulphurous acid Thioglycolic acid Trichloroacetic acid... 

Naphthoquinone-4-sulfonic Acid- Perchloric Acid - Formaldehyde Reagent... 

Naphthoquinone-4-sulfonic Acid-Perchloric Acid-Formaldehyde Reagent 353... 

The above difference in reactivity of benzene and toluene is close to that observed in a less viscous system so that the results for compounds of the reactivity of benzene (and perhaps toluene) or less in these media are meaningful, but not for compounds which are normally more reactive. This conclusion was confirmed for nitration in nitric acid-perchloric acid of a range of compounds which normally are fairly reactive. The derived second-order rate coefficients (10k2) for nitration... 

V-chloro compounds have also been used for the preparation of sulphones from sulphoxides. /V-chlorosuccinimide(NCS) oxidizes sulphoxides in aqueous acetic acid and acetic acid-perchloric acid mixtures. In purely aqueous media, the reaction is very slow and marked decomposition of the NCS occurs with no oxidation being evident105. 

Kinetic studies of the oxidation of diaryl sulfoxides by Crvi led to the proposition of a single electron transfer67 as in the case of aryl methyl sulfoxides68. These reactions were performed in aqueous acetic acid/perchloric acid medium, HCr03+ being the active... 

The reaction of the same compound with acetic acid-perchloric acid seems to proceed by an Se2 mechanism (lUPAC designation f/DEAn) ... 

If the dielectric constant of an amphiprotic solvent is small, protolytic reactions are complicated by the formation of ion pairs. Acetic acid is often given as an example (denoted here as AcOH, with a relative dielectric constant of 6.2). In this solvent, a dissolved strong acid, perchloric acid, is completely dissociated but the ions produced partly form ion pairs, so that the concentration of solvated protons AcOH2+ and perchlorate anions is smaller than would correspond to a strong acid (their concentrations correspond to an acid with a pK A of about 4.85). A weak acid in acetic acid medium, for example HC1, is even less dissociated than would correspond to its dissociation constant in the absence of ion-pair formation. The equilibrium... 

Nitric acid, Perchloric acid MRH Nitric acid 5.81/74... 

Ethylbenzene, Thallium triacetate Ucmura, S. et al., Bull. Chem. Soc., Japan., 1971, 44, 2571 Application of a published method of thallation to ethylbenzene caused a violent explosion. A reaction mixture of thallium triacetate, acetic acid, perchloric acid and ethylbenzene was stirred at 65°C for 5 h, then filtered from thallous salts. Vacuum evaporation of the filtrate at 60°C gave a pasty residue which exploded. This preparation of ethylphenylthallic acetate perchlorate monohydrate had been done twice previously and uneventfully, as had been analogous preparations involving thallation of benzene, toluene, three isomeric xylenes and anisole in a total of 150 runs, where excessive evaporation had been avoided. 

See Ethyl hydroperoxide Hydriodic acid Perchloric acid Iodides Potassium chlorate Hydrogen iodide... 

Iodoform Iodomethane Iron disulfide Isothiourea Ketones Lactonitrile Lead Acetone, lithium, mercury(II) oxide, mercury(I) chloride, silver nitrate Silver chlorite, sodium Water, powdered pyrites Acrylaldehyde, hydrogen peroxide, nitric acid Aldehydes, nitric acid, perchloric acid Oxidizing materials Ammonium nitrate, chlorine trifluoride, hydrogen peroxide, sodium azide and carbide, zirconium, oxidants... 

In this method approximately 19 samples of marine sediment were oven dried at 110°C then digested with nitric acid-perchloric acid and hydrofluoric acid-hydrochloric acid. The digested solution is made up to 50ml of an equal volume mixture of 6M hydrochloric acid and 2M nitric acid. 0.1ml or less of the digest was pipetted into the hydride generator, followed by 1ml 2M acetic acid, diluted to 100ml with double distilled water and reacted with sodium borohydride. 

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