摘要:

The standard molar volumes, the standard molar enthalpies of solution, and the limiting conductivities have been determined for potassium and tetrabutylammonium adamantylcarboxylates in water and heavy water, at 298.15 K. The temperature dependence of the volume and of the conductivity of the potassium salt has also been studied. The results are compared with those relative to potassium acetate. The change of the methyl group for the adamantyl one does not follow the behaviour normally expected for the transfer of hydrophobic solutes from water to heavy water.

ISSN:0008-4042    

DOI:10.1139/v79-108

出版商:NRC Research Press    

年代:1979

数据来源: NRC

摘要:

Densities, viscosities, enthalpies, and magnetic susceptibilities at 30 °C were determined for the system cumene +p-dioxane. From the experimental results, the excess viscosity, excess enthalpy, excess volume, and excess molar magnetic susceptibility were calculated. The excess functions show deviations from the additivity law. An attempt has been made to explain the observed deviations on the basis of intermolecular interactions.

ISSN:0008-4042    

DOI:10.1139/v79-109

出版商:NRC Research Press    

年代:1979

数据来源: NRC

摘要:

Bridged compounds, [Pt(L)Cl2]2(L = pyridine, picoline, and lutidine) have been prepared from the reactions between K[Pt(L)Cl3] and perchloric acid. The molecular weight measurements indicate that they are dimers in chloroform solutions. When [Pt(L)Cl2]2is dissolved in dimethylformamide (DMF), [Pt(L)(DMF)Cl2] is formed and has been isolated. Infrared and nmr studies have shown that DMF is coordinated to platinum through the oxygen atom.

ISSN:0008-4042    

DOI:10.1139/v79-110

出版商:NRC Research Press    

年代:1979

数据来源: NRC

摘要:

The heats of formation of decafluorocyclohexene and dodecafluorocyclohexane have been determined by the direct combustion method previously developed and used for hexafluorobenzene and related compounds. The combustion of decafluorocyclohexene and dodecafluorocyclohexane formed the reaction products CO2, CF4, and F2. In both cases a portion of the compound remained unburned. The unburned material was collected and quantitatively determined gravimetrically. A material balance was obtained for carbon and fluorine on the basis of CO2, CF4, and F2and the amount of unburned compound. With a ten-fold excess of oxygen, the average CO2-to-CF4molar ratios for C6F10and C6F12are 2.03 ± 0.01 and 1.35 ± 0.01, respectively. The values obtained for the heats of formation are ΔH0f298(C6F10,g) = −1906.6 ± 7.2 kJ mol−1and ΔH0f298(C6F12,g) = −2368.9 ± 7.6 kJ mol−1. ΔH0f298for the reaction C6F10(g) + F2(g) → C6F12(g)was calculated to be −462.3 ± 14.8 kJ mol−1and the 'resonance energy' of C6F6is estimated at −36.4 kJ mol−1.

ISSN:0008-4042    

DOI:10.1139/v79-111

出版商:NRC Research Press    

年代:1979

数据来源: NRC

摘要:

The pyrolysis of NH3was studied behind reflected shock waves at temperatures 2500–3000 K, using mass spectrometric analysis of dynamically sampled gas. The initial mixtures contained 0.14% to 6% NH3, with Kr as diluent, at total gas concentrations of about 2 × 10−6 mol cm−3. Concentration profiles of NH3, NH2, NH, and N2were measured. It was found that the apparent rate coefficient for overall removal of NH3is increased by increasing the initial NH3concentration, but is decreased by addition of H2. Addition of H2also suppressed NH, but left the NH2concentration relatively unchanged. A close correlation was found between NH2concentration and N2formation rate, indicating that NH2participates in the reaction which produces N2.The experimental results are consistent with a chain mechanism in which NH3is removed by unimolecular decomposition and by attack by H, NH, and NH2. Computer analysis yields a rate constant of 1.2 × 1016exp (−91 000 cal mol−1/RT) cm3mol−1s−1for the unimolecular process.

ISSN:0008-4042    

DOI:10.1139/v79-112

出版商:NRC Research Press    

年代:1979

数据来源: NRC

摘要:

The conductances, densities, and viscosities of concentrated solutions of ammonium chloride in water, at 25 °C, have been determined with good agreement with existing conductance data. The same data have been obtained for mixed solutions of indium trichloride and ammonium chloride. The fact that the conductance is always much less than the sum of the individual conductances, in some cases less than that of indium chloride alone, points to the existence of a complex in solution.

ISSN:0008-4042    

DOI:10.1139/v79-113

出版商:NRC Research Press    

年代:1979

数据来源: NRC

摘要:

The density up to 257 °C and the vapour pressure up to 189 °C of dimethylsulfoxide have been determined directly. Dimethylsulfoxide decomposes below the critical temperature, but by indirect methods the (hypothetical) critical density is found to beorThe vapour pressure measurements yield a molar heat of evaporation of 10.84 kcal/mol or 138.7 cal/g

ISSN:0008-4042    

DOI:10.1139/v79-114

出版商:NRC Research Press    

年代:1979

数据来源: NRC

摘要:

A total synthesis of (−)-khusimone (1), an odoriferous norsesquiterpenoid ketone, has been achieved in 16 steps from the ammonium salt ofl-10-camphorsulfonic acid.

ISSN:0008-4042    

DOI:10.1139/v79-115

出版商:NRC Research Press    

年代:1979

数据来源: NRC