Determination of sodium sulphate, calcium chloride and sodium chloride in gypsum plaster

Summary It has been shown that chloranilic acid and its salts can be used to determine sodium sulphate in the presence of calcium sulphate, calcium chloride in the presence of calcium sulphate, and sodium chloride in the presence of calcium chloride. The analysis is direct, the separation from non-desired components being carried out at the same time as the determination itself.One aspect of the use of chloranilic acid should be stressed, namely, that it sometimes is possible to differentiate between two salts that have the same anion but different cations, and examples have been given in this paper.     

Dissociative attachment in vinyl and allyl chloride,chlorobenzene and benzyl chloride

Relative cross sections for dissociative attachment are measured in vinyl and allyl chloride, chlorobenzene and benzyl chloride. For each pair, the compound with the Cl located out of the π nodal plane yields the larger cross section, by a factor of 5.3 and 17.5 respectively. In each case the maximum in the cross section occurs within 100 meV of the lowest π¹ resonance located by electron transmission spectroscopy.     

Thermodynamics of aqueous mixtures of sodium chloride,potassium chloride,sodium sulfate,and potassium sulfate at 25°C

Aqueous solutions of sodium chloride, potassium chloride, sodium sulfate, and potassium sulfate can be mixed in six ways to give ternary mixtures. Two of these have already been studied and results are now presented for the remaining four systems: H₂O–NaCl–K₂SO₄, H₂O–Na₂SO₄–K₂SO₄, H₂O–KCl–Na₂SO₄, and H₂O–KCl–K₂SO₄.     

Friedel–Crafts polymerization of fluorene with methylene chloride,methoxyacetyl chloride,and chloromethyl methyl ether

The polymerization of fluorene with various chloromethylating reagents (methylene chloride, methoxyacetyl chloride, and chloromethyl methyl ether) in the presence of aluminum chloride was studied. The products that were obtained were insoluble, infusible, colored powders which contain a low concentration of aromatic radicals. Each of the polymers is composed predominantly of fluorene nuclei bridged at the 2 and 7 positions by methylene groups. In addition, the materials possess varying amounts of crosslinked and ring-fused moieties. Based on physical and spectral properties and reaction stoichiometry, the fluorene/methylene chloride polymer is the most highly crosslinked of the three. The fluorene/methoxyacetyl chloride and fluorene/chloromethyl methyl ether polymers are similar to each other in most respects.     

On the electronic and molecular structures of methyl chloride,cyclopropyl chloride and 1,1-dichlorocyclopropane

Ab initio SCF—MO calculations have been carried out on cyclopropyl chloride and 1,1-dichlorocyclopropane, to illuminate the effect of the substituent upon the cyclopropane ring. For cyclopropyl chloride, reasonable agreement is found with experimental findings. For 1,1-dichlorocyclopropane, excellent agreement is found with the results from a recent NMR study. As a means of studying the effect of a change in basis set, calculations are also carried out on methyl chloride.     

Copolymerization of N-vinylpyrrolidone with N,N-dimethyl-N,N-diallylammonium chloride

The possibility of synthesizing copolymers of N,N-dimethyl-N,N-diallylammonium chloride (DMDAAC) and N- vinylpyrrolidone (VP) was demonstrated and the features of radical copolymerization of these monomers in aqueous and alcohol media were investigated. The optimum conditions of conducting the reaction were determined and the kinetic features of the copolymerization reaction in the region of low degrees of conversion, for which the usual order mechanisms for radical polymerization are preserved, were investigated. The dependence of the initial rate of co polymerization on the composition of the starting mixture of comonomers is nonlinear, and the rate of copolymerization decreases significantly as the concentration of DMDAAC in the starting mixture increases. The composition of copolymers formed was studied and the copolymerization constants r₁ ^ef=r₂ ^ef=1 were calculated, i.e., the system is azeotropic, which is also detected for significant degrees of conversion.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 1969–1973, September, 1990.     

Reaction of ethanesulfenyl chloride with N,N-diethylethanesulfenamide

Conclusions The reaction of N,N-diethylethanesulfenamide with ethanesulfenyl chloride or with diethylamine hydrochloride leads to the formation of N,N-diethyl-,-bis(ethylthio)vinylamine, diethyl disulfide, anddiethyl trisulfide.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2499–2503, November, 1971.     

Excess gibbs energies of aqueous mixtures of sodium chloride,potassium chloride,sodium acetate,and potassium acetate at 25°C

Measurements have been made on the systems NaCl?NaOAc, NaOAc?KOAc, KCl?KOAc, NaCl?KOAc, and KCl?NaOAc. The results are consistent with binary Na?K and Cl?OAc interactions, and there is no evidence for triple-ion interaction.     

Trifluoromethanesulfonyl chloride,a mild chlorinating agent

Carbon acids (pK_A range: dialkyl malonate → methyl dichloroacetate) are efficiently chlorinated with CF₃SO₂Cl/NEt₃, even in the presence of alcohols.     

Telomerization of vinyl chloride by benzyl chloride

Conclusions The systems Fe(CO)₅ + hexamethylphosphotriamide and Fe(CO)₅ + DMF are efficient initiators for the telomerization of vinyl chloride by benzyl chloride involving the C-Cl bond of the benzyl chloride, in which connection both the conversion of the telogen and yield of telomers is high. Telomers of general formula C₆H₅CH₂-(CH₂CHCl)_nCl (n=1–3) were isolated.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2541–2546, November, 1980.     

Determination of (2,3-epoxypropyl)trimethylammonium chloride, (3-chloro-2-hydroxypropyl)trimethylammonium chloride, and (2,3-dihydroxypropyl)trimethylammonium chloride by capillary electrophoresis

Capillary electrophoresis (CE) is a powerful technique to determine (2,3-epoxypropyl)trimethylammonium chloride, (3-chloro-2-hydroxypropyl)trimethylammonium chloride and their hydrolysis product (2,3-dihydroxypropyl)trimethylammonium chloride in complex matrices. The separation was performed in a 180 mM copper(II) sulphate-4 mM formic acid buffer at pH 3. The UV inactive target compounds were detected by indirect UV detection at 215 nm with a reference wavelength of 300 nm--copper(II) being the chromophor. The results were compared to data acquired by ion-pair HPLC with perchlorate as ion pair former in a 1 M aqueous sodium perchlorate solution in 0.2 mM phosphoric acid (pH 3.4) on a RP 18 column and refractive index detection as reference method. Results of both methods are in good agreement.     

2, 3, 5, 6-Tetrachlorpyridine-4-sulfenyl chloride

2,3,5,6-Tetrachloropyridine-4-sulfenyl chloride has been prepared, and its reactions with nucleophilic reagents have been examined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp 1232–1235, September, 1970.     

The formation,growth, and stability of silver chloride sols

A mechanistic investigation of sol formation by precipitation from homogeneous solution has been performed by interpretation of conductivity data. Initiation of growth occurred by heterogeneous nucleation upon impurity particles of approximate average radius 20 å and continued by a surface controlled process. In the later stages of growth, sedimentation and changes in colloidal stability affected the growth rate and the concentration of silver and chloride ions producing zero point charge in supersaturated solutions could readily be calculated.     

Copolymerization of N,N-diallyl-N,N-dimethylammonium chloride and vinyl acetate

The free-radical copolymerization of N,N-diallyl-N,N-dimethylammonium chloride with vinyl acetate in DMSO, methanol, and a methanol-water (70: 30, mol %) mixture proceeds to yield statistical copolymers. The nature of solvents significantly affects the reactivity ratios of the comonomers. N,N-Diallyl-N,N-dimethylammonium chloride shows a higher reactivity than vinyl acetate. The kinetic features of the processes have been investigated, and the structure and properties of the copolymers have been studied.