Liquid Ammonia Solutions Research Articles

Liquid ammonia solutions. XI. Raman study of the nature of solutions containing alkali and alkaline earth cations

Liquid ammonia solutions. XI. Raman study of the nature of solutions containing alkali and alkaline earth cations

Changes of cellulose accessibility to reactions in alkaline medium by activation with ammonia

AbstractThe effect of activation of cellulose by ammonia is surveyed with regard to an increase of accessibility of different cellulose structures to subsequent reactions proceeding in an alkaline medium, causing considerable swelling by itself. Special subjects were the reactions of xanthogenation, carboxymethylation, and cyanoethylation. In all these heterogeneous reactions a considerable increase in the reaction rate and degree of conversion was found.Using the emulsion xanthogenation with a stepwise enlargement of NaOH concentration as a method of accessibility measurement, considerable changes of the accessibility spectrum of different cellulose structures were found after activation with liquid ammonia or aqueous solutions of ammonia at high concentration. In all the cases investigated, the activation brings about a considerable broadening of the accessibility distribution.

Kinetics of electrode reactions in liquid ammonia. Part 3.—The silver electrode in acid solution

The behaviour of the silver electrode in acid solutions of liquid ammonia has been studied by steady and non-steady state electrochemical measurements and electron microscopy. The apparent rate constant and standard potential have been determined. The rate-determining step in silver deposition and dissolution is the charge transfer reaction which is probably coupled with an adatom diffusion mechanism. Oxidised species originating from the solvent are adsorbed on silver except at cathodic values of electrode potential. The anodic behaviour of silver is complicated by the formation of anodic deposits, probably silver nitride, in parallel with the metal dissolution reaction. By making comparisons with silver electro-deposition from simple and cyanide aqueous baths it is concluded that the adsorbed solvent decomposition products are responsible for the poor quality of deposits from ammoniacal electrolytes.

ChemInform Abstract: LIQUID AMMONIA SOLUTIONS PART 10, A RAMAN STUDY OF INTERACTIONS IN THE LIQUID STATE

Chemischer InformationsdienstVolume 4, Issue 45 Physical Inorganic Chemistry ChemInform Abstract: LIQUID AMMONIA SOLUTIONS PART 10, A RAMAN STUDY OF INTERACTIONS IN THE LIQUID STATE A. T. LEMLEY, A. T. LEMLEYSearch for more papers by this authorJ. H. ROBERTS, J. H. ROBERTSSearch for more papers by this authorK. R. PLOWMAN, K. R. PLOWMANSearch for more papers by this authorJ. J. LAGOWSKI, J. J. LAGOWSKISearch for more papers by this author A. T. LEMLEY, A. T. LEMLEYSearch for more papers by this authorJ. H. ROBERTS, J. H. ROBERTSSearch for more papers by this authorK. R. PLOWMAN, K. R. PLOWMANSearch for more papers by this authorJ. J. LAGOWSKI, J. J. LAGOWSKISearch for more papers by this author First published: November 6, 1973 https://doi.org/10.1002/chin.197345030Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume4, Issue45November 6, 1973 RelatedInformation

Resolution of theoptical spectra of sodium solutions in liquid ammonia into two experimentally unresolvable bands

Spectra of the solvated electron were determined at --55, -65, and --75 deg C for solutions in NH/sub 3/ and in NH/sub 3/ 0.08 M in Nal by extrapolations to inflnite dilution. Spectra obtained for Na-NH/sub 3/ solutions and for Na-NH/ sub 3/-Nal solutions were shown to fulflll the expectations of a two absorber model. The data rule out the possibility that the second absorber incorporates only a single solvated electron. The data support the assumption that the second absorber involves a binary combination of solvated electrons. Spectra of the second absorber are obtained at all three temperatures and for solutions in both NH/sub 3/ and in NH/sub 3/ 0.08 M in Nal. Spectra due to Gold and Jolly appear to be characteristic of the second absorber and not the solvated electron. (auth)

The reaction of hydrogen with copper(I) in liquid ammonia-amide solutions

Molecular hydrogen reacts with liquid ammonia solutions containing CuI and excess of either KNH 2 or CsNH 2 to form thermally unstable orange-red solids with the approximate compositions K 2Cu 3H 5 · xNH 3 and CsCuH 2 · xNH 3. The compounds have been characterized by elemental analysis, X-ray powder diffractometry, and, in the case of the potassium compound, Raman spectroscopy and magnetic measurements.

Ferromagnetism in Eu intercalated NbS 2

The layered compound NbS 2 can be intercalated with Eu, Yb and Sr from liquid ammonia solution at low temperatures. The intercalated species are predominantly divalent ions and produce an expansion in c axis of ∼ 3A. Eu x (NH 3) y NbS 2 (x ≥ y) compounds with x ≳ 0.4 order ferromagnetically below 8°K. Diamagnetic intercalated species lower the superconducting transition temperature of pure NbS 2 whereas paramagnetic species completely destroy the effect. High temperature reactions of Eu with NbS 2 always produce ferromagnetic EuS as an impurity phase and obscure the inherent low temperature properties of Eu intercalated NbS 2.

Liquid ammonia solutions. X. Raman study of interactions in the liquid state

Liquid ammonia solutions. X. Raman study of interactions in the liquid state

Infrared and Raman spectra of lithium and ammonium nitrate solutions in liquid ammonia

Vibrational spectra, most of them obtained from Raman scattering, are reported for LiNO3 and NH4NO3 solutions in liquid ammonia, ranging from dilute to the compositions LiNO3/1.6NH3 and NH4NO3/1NH3. All the spectra were obtained from solutions at ambient temperatures. Large changes in the N–H stretching region are correlated with the effects of the electrolytes on the solvent structure. Low-frequency bands associated with Li–NH3 modes are identified. Spectral features indicative of both solvent-separated and contact ion pairs involving Li+ and NO3− are analyzed. Contact ion pairing between NH4+ and NO3− ions in this solvent fails to produce any measurable splitting of the NO3− ν3(E′) or ν4(E′) modes.

Proton Transfer in Liquid Ammonia Solutions Containing Water and Hydroxide Ion

AbstractThe rate of proton transfer in ammonia solutions containing water and hydroxide ion was determined as a function of temperature and concentration by means of PMR spectroscopy. A first order dependence on hydroxide ion and second order dependence on water concentration was found with a rate constant of k3 = 6.1 ± 1.2 × 103 M−2 sec−1 at 25°C and ΔE‡ = 4.5 ± 0.5 kcal/mole. The value of k3 is in good agreement with that reported by other workers.

Vapor Pressure and Solubility of the Sulfuryl Diamide-Ammonium Thiocyanate-Ammonia Systemt

Vavpor pressure and solubility of the ternary sulfuryl diamide-ammonium thiocyanateammonia system were investigated at O, 10, and 20C.The vapor pressure was determined for the Iiquid ammonia solutions of NH2SOaNH NH4SCN mixture having a weight ratio of 3 1, 1 1, and 1 3 and the liquid ammonia solution saturated with respective solid components.The vapor pressure of liquid ammonia is greatly lowered by the dis olution of NHaSO2NHx and NH4SCN. The liquid ammonia solution saturated with both solid shows the lowest vapor pressur among the ternfic ry solutions, having a vapor pressure of 57 mmHg 70mmHg 20eC, 90 mmHg.The solubility isotherms of the system NH2SO2NH2 NH4SCN NHs at OC, 10C, and 20C are found to be simple. The pure NH2SO2NH2 and NH4SCN remains as solid phase. The isothermally invariant ternary solution saturated with both solid has a solubility of 379 g NH2SO2NH2 and 354 g NH4SCN at 472 g NH2SO2NH2 and 419 g NH, SCN at 100C, and 640g NH2SO, NH2 and 510 g NH4SCN at 20C for 100 g liquid ammonia respectivcly.

Raman spectra of liquid ammonia solutions of metal salts

Liquid ammonia solutions of simple metal salts give good Raman spectra with little interference from solvent bands; the metal–nitrogen stretching vibrations indicate unusual co-ordination numbers with Zn2+, Hg2+, and Ag+, and ion-association effects are smaller than in aqueous solutions.

Electron spin resonance studies of reduction by solvated electrons in liquid ammonia. Part 7.—α,β-unsaturated carboxylic acids, esters and nitriles

The technique of continuously mixing liquid ammonia solutions of solvated electrons (obtained by dissolving sodium) and a substrate in the cavity of an e.s.r. spectrometer has been applied to both acrylic acid and its homologues and the corresponding esters and also unsaturated dicarboxylic acids, all of which give rise to the radical-anion of the substrate. The radical-anion of trans-crotonitrile has also been characterised.With certain esters, s-cis- and s-trans-conformations of the radical-anion have been observed and the radical-anions of the esters of maleic and fumaric acids have been shown to interconvert. Assignment of coupling constants has been made by systematic substitution of protons by alkyl groups, etc., and confirmed both by simple MO calculations and by the INDO method. Reduction of acetylenic to ethylenic bonds has been observed on the ms timescale for phenylpropiolic acid and ethyl propiolate and anomalous spectral linewidths have been noted in the e.s.r. spectrum of the latter.

The preparation of anhydrous lanthanide cyanides

The reaction between NH 4CN and liquid ammonia solutions of Ce, Pr, Sm, Ho, Eu and Yb yields simple cyanides of the composition Ce(CN) 3, Pr(CN) 3, Ho(CN) 3, Sm(CN) 3, Sm(CN) 2, Eu(CN) 3, Eu(CN) 3, Yb(CN) 3 and Yb(CN) 2. An alternative route to these compounds using Hg(CN) 2 has been investigated. Some chemical properties, infrared and X-ray data are reported.

Raman Study of the Effect of NaClO4and NaI on the Hydrogen-Bonded Structure of Liquid NH3

Abstract Recent studies1,2 of the Raman spectra of liquid ammonia have been in disagreement with regard to the assignment of bands in the 3000 cm−1 region. This region is complicated by Fermi resonance between the ν1 (A1) fundamental stretching mode and the 2ν4 (A1) overtone of the bending mode. In an effort to help clarify these assignments and to study further the structure of liquid ammonia, it was decided to measure the Raman spectrum of several salt solutions in liquid ammonia.

Vapor Pressure of Sulfuryl Diamide-Ammonia systems

Vapor pressure and density of sulfuryl diamide-ammonia system were measured between -10 and -30°C.The vapor pressures for saturated liquid ammonia solutions of sulfuryl diamide were 248 mmHg at -10°C, 350 mmHg at 0°C, 485 mmHg at 10°C, 637 mmHg, at 20°C, respectively, and the densities of these saturated solutions were about 1.4. The vapor pressures, obtained for various concentrations of sulfuryl diamide-ammonia soultions (Tables 1 and 3), conformed to the simplified Clausius-Clapeyron equation, logp.=A/T+C, where p is vapor pressure, T is temperature in °K, and A and C are constants.

Electrolyte solutions in liquid ammonia—III: The use of hydrogen electrodes

An apparatus is described with which it is possible to operate hydrogen gas electrodes on platinum in ammonium salt solutions in liquid ammonia. These electrodes have been shown to be reversible and to give stable, reproducible and accurate e.m.f.'s at −40°C over prolonged periods of time after an initial settling down period of 4–6 hr. The work proves conclusively that it will be possible to use hydrogen-on-platinum half-cells as primary standards for electrode potentials in liquid ammonia. E.M.F. data for the concentration cell with transference, Pt H 2 | NH 4 NO 3m 2| Pt H 2 in liquid ammonia, are given. From these data it is possible to assess the ammonium ion activities and concentrations over a wide range of concentrations of ammonium nitrate. The free energies of dilutions of ammonium nitrate in liquid ammonia from 10 −2 molal to several other concentrations are given.

Experiments Concerning Electrochemical Production of solvated Electrons

Abstractsolvated electrons are known to be produced by electrolysis of liquid ammonia solutions of alkali salts. It is doubtful however if solvated electrons also are formed as precursor of hydrogene during electrolysis of aqueous solutions.Experiments were undertaken to detect by optical means solvated electrons injected into liquid water or ammonia by cathodic polarisation of a light reflecting silver electrode. The experimental set up allowed us to detect changes of 1 · 10−6 in intensity of the reflected light which would be connected with the concentration of 3 · 10−14 mol hydrated electrons per cm2 electrode surfaces.In aqueous solutions the intensity of the reflected light changes with cathodic polarisation of the electrode. The dependence of this effect on the wave length of the reflected light however rules out the hypothesis that it is due to solvated electrons formed as intermediate during electrolysis. On the other hand in liquid ammonia the effects are larger by several orders of magnitude and show the wave length dependence as expected for ammoniated electrons.

Ytterbium(II) amide

The reaction of ytterbium metal with ammonia gas at elevated pressure yields ytterbium(II) amide, in contrast to the reaction with liquid ammonia, which yields a di- and tri-amide mixture. The Yb(NH 2) 2 was characterized by i.r. spectra, X-ray diffraction, and magnetic susceptibility. The equilibrium constant for the reaction Yb(NH 2) 2 + NH 2 − = Yb(NH 2) 3 + e − was found to be 200 ± 100, and the reduction potential for Yb(III)/Yb(II) in basic liquid ammonia solution−2·10 ± 0·05V.

Differential capacitance and frequency dispersion on solid and liquid mercury in liquid ammonia

The behaviour of solid and liquid mercury electrodes in 0·1 M ammonium nitrate solutions of liquid ammonia is investigated. The differential-capacitance/potential curves for the solid (at −40°C) and the liquid (at −38°C) are U-shaped and have a minimum of 11·2 μF/cm 2 at 0·45 V ( vs Cd/satd. Cd(NO 3) 2 in liquid NH 3) for the solid of and 10·25 μF/cm 2 at 0·4 V for the liquid. The curves have no anodic hump. The values for the solid are about 10% higher than that for the liquid but this is still within the error of the surface area measurement. The frequency dispersion of the interfacial impedance was measured between 400 and 20,000 Hz at 0·60, 0·40, 0·10, and −0·25 V. Assuming de Levie's model of parallel grooves of depth l and aperture 2 β to be applicable, the parameter l/sin β was calculated from the data. Values obtained for the liquid mercury electrodes are 5·5–6·8 × 10 −2 cm and are attributed to shielding and solution creepage. For the solid electrodes l/sin β is 12–23 × 10 −2cm. Although these numbers are too large, the increase in l/sin β by a factor of 3 when going from a liquid to a solid surface is parallel to an increase in roughness factor to about 3 expected for this case. This suggests that l/sin β may be a useful way to measure surface roughness and/or surface roughness changes.