Chloride mixture

This experiment uses the molybdenum-blue method to determine the concentration of phosphate in a phosphate/sodium chloride mixture. Elow-injection analysis is used to increase the speed of analysis, allowing students to... 

Dimethyl carbonate [616-38-6] and dimethyl oxalate [553-90-2] are both obtained from carbon monoxide, oxygen, and methanol at 363 K and 10 MPa (100 atm) or less. The choice of catalyst is critical cuprous chloride (66) gives the carbonate (eq. 20) a palladium chloride—copper chloride mixture (67,68) gives the oxalate, (eq. 21). Anhydrous conditions should be maintained by removing product water to minimize the formation of by-product carbon dioxide. 

Product Recovery. The aHyl chloride product is recovered through the use of several fractional distillation steps. Typically, the reactor effluent is cooled and conducted into an initial fractionator to separate the HCl and propylene from the chloropropenes, dichloropropanes, dichloropropenes, and heavier compounds. The unconverted propylene is recycled after removal of HCl, which can be accompHshed by adsorption in water or fractional distillation (33,37,38) depending on its intended use. The crude aHyl chloride mixture from the initial fractionator is then subjected to a lights and heavies distillation the lighter (than aHyl chloride) compounds such as 2-chloropropene, 1-chloropropene, and 2-chloropropane being the overhead product of the first column. AHyl chloride is then separated in the second purification column as an overhead product. Product purities can exceed 99.0% and commercial-grade aHyl chloride is typicaHy sold in the United States in purities about 99.5%. 

The exchange of aromatic protons can be effected in the absence of any -OH or —NH2 activating group during the course of a Clemmensen reduction in deuteriochloric and deuterioacetic acid mixture (see section Ill-D). This reaction has been carried out with various tricyclic diterpenes and is best illustrated by the conversion of dehydroabietic acid into its 12,14-d2-labeled analog (40 -+ 41).Amalgamated zinc is reportedly necessary for the exchange reaction since the results are less satisfactory when a zinc chloride-mercuric chloride mixture is used. 

Binary mixtures that melt close to room temperature, namely AlCl3/N-butylpyri-dinium chloride mixtures, have also been investigated. Takahashi et al. [17] have also shown that for the 1 1 composition, [AlClJ predominates with a tetrahedral environment. At a ratio of 2 1, [Al2Cl7] becomes the main species. At high temperature (above 150 °C), some decomposition to [AlClJ and Al2Cl(3 was observed. 

The ratio of the chloride mixture mainly derives from the toluene/chlo-rine ratio and the contact time. Benzyl chloride is produced hy passing dry chlorine into hoiling toluene (110°C) until reaching a density of 1.283. At this density, the concentration of henzyl chloride reaches the maximum. Light can initiate the reaction. 

Not all sulphates are as readily reduced as sodium sulphate, for instance, calcium sulphate does not usually lead to sulphide penetration, although the presence of other substances with calcium sulphate may lead to accelerated oxidation for other reasons. The results for laboratory tests on a series of metals and alloys in sodium sulphate -F sodium chloride and calcium sulphate + calcium chloride mixtures are shown in Table 7.12 . In many cases sulphide peneration could be noted with the sodium salts but not with the calcium salts. 

SILVER / SILVER CHLORIDE MIXTURE. SILVER FINELY -DIVIDED... 

An immediate application of the use of the aqueous ammonia-ammonium chloride mixture may be made to the familiar example of the prevention of precipitation of magnesium hydroxide (S.P. 1.5 x 0-11). We can first calculate the minimum hydroxide ion concentration necessary to prevent precipitation in, say, 0.1M magnesium solution. 

Solid-surface room-temperature phosphorescence (RTF) is a relatively new technique which has been used for organic trace analysis in several fields. However, the fundamental interactions needed for RTF are only partly understood. To clarify some of the interactions required for strong RTF, organic compounds adsorbed on several surfaces are being studied. Fluorescence quantum yield values, phosphorescence quantum yield values, and phosphorescence lifetime values were obtained for model compounds adsorbed on sodiiun acetate-sodium chloride mixtures and on a-cyclodextrin-sodium chloride mixtures. With the data obtained, the triplet formation efficiency and some of the rate constants related to the luminescence processes were calculated. This information clarified several of the interactions responsible for RTF from organic compounds adsorbed on sodium acetate-sodium chloride and a-cyclodextrin-sodium chloride mixtures. Work with silica gel chromatoplates has involved studying the effects of moisture, gases, and various solvents on the fluorescence and phosphorescence intensities. The net result of the study has been to improve the experimental conditions for enhanced sensitivity and selectivity in solid-surface luminescence analysis. 

Sodium Acetate-Sodium Chloride Mixtures. Ramasamy and Hurtubise (12) obtained RTF and RTF quantum yields, triplet formation efficiency, and phosphorescence lifetime values for the anion of p-aminobenzoic acid adsorbed on sodium acetate and on several sodium acetate-sodium chloride mixtures. Rate constants were calculated for phosphorescence and for radiationless transition from the triplet state. The results showed that several factors were important for maximum RTF from the anion of p-aminobenzoic acid. One of the most important of these was how efficiently the matrix was packed with sodium acetate molecules. A similar conclusion was found for RTF however, the RTF quantum yield increased more dramatically than the RTF quantum yield. 

Elf Atochem NA (1996) Toxicity of a methyltin chloride mixture in rats. Homer, NY, ClinTrials BioResearch (CTBR), for Elf Atochem North America (Project No. 97307). 

G. j. Janz, R. P. T. Tomkins, C. B. Allen, J. R. Downey, Jr., G. L. Gardener, U. Krebs, and K. Singer, J. Rhys. Chem. Ref Data 4 (1975) 871 Molten Salts, Vol. 4, Part 2 Chloride Mixtures, American Chemical Society-American Institute of Physics-National Bureau of Standards, Washington, DC, 1975. 

Carbon tetrachloride/triethyialuminium/aluminium chloride mixture is explosive at a temperature of 20°C. 

Aluminium chloride has to be introduced gradually in the naphthalene/benzoyl chloride mixture and the mixture of these two reagents has to be brought to a temperature that is high enough so that it is in the molten state. Crystallised naphthalene residues are enough to cause the medium to detonate. 

Palite Chloromethyl Chloroformate and Stannic Chloride Mixture ... 

A nucleophilic attack at an allene system of the type of 417 was described for the first time by Cainelli et al. [172], namely at 444 with the chloride ion as the nucleophile (Scheme 6.91). After the treatment of the mesylate 443 with triethylamine in the presence of lithium, sodium or tetrabutylammonium chloride, mixtures of the vinyl chlorides 445 and 447 were isolated in high yields. Since the reaction did not proceed in the absence of triethylamine, the first step should be a /3-elimination of methanesulfonic acid from 443 to generate 444, which would accept a chloride ion at the central allene carbon atom. A proton transfer to either allyl terminus of the anion thus formed (446) would lead to the products 445 and 447. 

In view of the utility of the aromatic polyesters and the demonstrated effectiveness of the aromatic polyphosphonates as flame retardants, the combination of these two polymers was chosen for this study. In addition, this system provided a composition in which both copolymers and polymer blends could be prepared with identical chemical compositions. The polyesters were prepared from resorcinol with an 80/20 m/m ratio of iso-phthaloyl and terephaloyl chlorides while the polyphosphonates were resorcinol phenylphosphonate polymers. Copolymerized phosphorus was incorporated by replacement of a portion of the acid chloride mixture with phenylphosphonic dichloride. 

Preparation of Phosphorus Containing Terpolymers. Prepared by substitution of a portion of the acid chloride mixture by a calculated amount of phenyl phosphonic dichloride. The compositions of these polymers are summarized in Table 1. 

TN. Dymova, N.N. Mal tseva, V.N. Konoplev, A.I. Golovanova, D.P. Alexandrov, A.S. Sizareva, Solid-phase solvate-free formation of magnesium hydroaluminates Mg(AlH )2 and MgAlHj upon mechanochemical activation or heating of magnesium hydride and aluminum chloride mixtures , Russ. J. Coord. Chem. 29 (2003) 385-389. 

Dibromo-1,2-dimethyl-l,2-epoxycyclohexane. Into a 1-1. three-necked flask fitted with an efficient stirrer, an alcohol fliermometer, a dropping funnel, and a drying tube are placed 32 g. (0.26 mole) of the epoxide and 500 ml. of an anhydrous ehloroform-methylene chloride mixture (1 1). The solution is cooled to —65° and 34 g. (0.21 mole) of bromine in 50 ml. of the siiine solvent is added dropwise while maintaining the temperature below —60° (Note 10). When the addition is complete, the reaction mixture is stirred for 30 minutes and the solvent is removed at room temj)eruturc under re[Pg.114]

Roll the aluminum foil loosely into a ball. Do not tightly pack the aluminum. Place the foil ball in the copper(II) chloride mixture. Let the reaction proceed for about 15 min. Make and record as many observations as possible of the reaction mixture. 

HPLC analysis of this product usually shows it to contain less than 1% of other calixarenes. If these are present in greater amounts (usually the cyclic tetramer, cyclic heptamer or cyclic octamer), their content can be reduced to less than 1% by triturating the product with hot acetone. The purity of the product can be qualitatively checked with TLC using a petroleum ether (30-60°C)/methylene chloride mixture (1 1) as eluant. The Rf of the cyclic hexamer is ca. 0.65, and the appearance of any spots with greater than 0.1 indicates the presence of other calixarenes. 

Several other processes also are apphed for the commercial production of europium. In general, all processes are based upon the initial steps involving opening the mineral (bastnasite or monazite) with sulfuric acid or sodium hydroxide, often followed by roasting and solubihzation. In one such process after separation of cerium, the soluble rare earth chloride mixture in HCl solution is pH adjusted and treated with bis(2-ethylhexyl)phosphate to obtain europium sesquioxide, EuaOs. 

The CMC of this new surfactant is several orders of magnitude lower than the CMC of its parent species. Figure 15 indicates a typical CMC plot versus the composition of the anionic-cationic (e.g., dodecyl sulfate-tetradecyl trimethyl ammomnium chloride) mixture in water. It can be seen that the CMCs of the anionic and cationic species are quite high, e.g., around 0.1 wt. %. As soon as a very small percentage of cationic is added to an anionic solution, the CMC falls several orders of magnitude. The same happens when a very small amount of anionic is added to a cationic solution. In both cases it seems that an equimolar catanionic species forms, and that its very low CMC dominates the mixing rule [84]. 

The surface tension y of the aqueous solution of dodecylammonium chloride — decylammonium chloride mixture was measured as a function of m at a given value of the mole fraction X of DeAC at 298.15 K under atmospheric pressure. The results are shown in Figure 1. It is seen that the y vs. m curves are similar in appearance. This behavior is in harmony with that observed previously in a low concentration range (9). Moreover, the formation of micelle is found to cause the curves to break sharply at the CMC which increases with X. It should be noted, however, that the y vs. m curve of a mixture has a very shallow minimum in the immediate vicinity of the CMC. 

An unusual reaction leading to the formation of 4-thioxopyrazolo[3,4-d]-pyrimidines has been reported. 1-Substituted 4-cyano-5-aminopyrazoles (103, R = H) react with phenyl isothiocyanate in dimethylformamide (DMF) saturated with hydrogen chloride to yield 1-substituted 4(5//)-pyrazolo[3,4-d]-pyrimidinethione (110). A proposed reaction sequence involved an initial nucleophilic addition of phenyl isothiocyanate to the protonated o-amino-nitrile to give an o-aminothioamide (108), followed by formylation by the dimethylformamide-hydrogen chloride mixture affording 109, which then cyclizes to the final product 110 (70MI1). 

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