Showing papers in "Journal of Physical and Chemical Reference Data in 1991"
TL;DR: In this article, the authors present a new equation of state in the form of a fundamental equation explicit in the Helmholtz free energy for thermodynamic properties of methane which were available up to the middle of 1991 and presents a new strategy for optimizing the structure of empirical thermodynamic correlation equations.
Abstract: This work reviews the data on thermodynamic properties of methane which were available up to the middle of 1991 and presents a new equation of state in the form of a fundamental equation explicit in the Helmholtz free energy. A new strategy for optimizing the structure of empirical thermodynamic correlation equations was used to determine the functional form of the equation. The Helmholtz function containing 40 fitted coefficients was fitted to selected experimental data of the following properties: (a) thermal properties of the single phase (pρT) and (b) of the liquid‐vapor saturation curve (psρ’ρ‘) including the Maxwell criterion, (c) speed of sound w, (d) isochoric heat capacity cv, (e) isobaric heat capacity cp, (f) difference of enthalph Δh, and (g) second virial coefficient B. Independent equations are also included for the vapor pressure, the saturated liquid and vapor densities, the isobaric ideal gas heat capacity and the melting pressure as functions of temperature. Tables for the thermodynamic ...
928 citations
TL;DR: In this paper, a model based on Henry's law was used to correlate the low pressure data (those up to 1 MPa) and the following correlation of the Henry's constants (expressed on a mole fraction basis) was developed ln(H21/MPa)=−6.8346+1.2817×104/T−3.7668×106/T2 +2.997×108/T3.
Abstract: The system carbon dioxide‐water is of great scientific and technological importance. Thus, it has been studied often. The literature for the solubility of carbon dioxide in water is vast and interdisciplinary. An exhaustive survey was conducted and approximately 100 experimental investigations were found that reported equilibrium data at pressures below 1 MPa. A model based on Henry’s law was used to correlate the low pressure data (those up to 1 MPa). The following correlation of the Henry’s constants (expressed on a mole fraction basis) was developed ln(H21/MPa)=−6.8346+1.2817×104/T−3.7668×106/T2 +2.997×108/T3 The correlation is valid for 273
585 citations
TL;DR: In this paper, a table is given of the compounds of low volatility whose experimental solubilities in supercritical carbon dioxide have been published up to the end of 1989, with the temperature and pressure ranges of the experimental measurements, the experimental method, and references to the source of data.
Abstract: A table is given of the compounds of low volatility, whose experimental solubilities in supercritical carbon dioxide have been published up to the end of 1989, with the temperature and pressure ranges of the experimental measurements, the experimental method, and references to the source of data. The data for pure compounds, which were presented in tabular form in the original publications, are shown in a series of figures along with correlation lines for each isotherm. The method of correlation was to fit the experimental data for each isotherm, in the form of the natural logarithm of the product of mole fraction and pressure, to a linear function of density above a pressure of 100 bars. The constants obtained from the fitting procedures are given in a table. Procedures for estimating, from these constants, the solubilities of the compounds at temperatures and pressures different from those of the experimental data are suggested.
557 citations
TL;DR: In this paper, cross sections for elastic, excitation, and ionization collisions of N+, N+2, N, and N2 with N2 and for Ar+ and Ar with Ar for laboratory energies from 0.1 eV to 10 keV are presented.
Abstract: Graphical and tabulated data and the associated bibliography are presented for cross sections for elastic, excitation, and ionization collisions of N+, N+2, N, and N2 with N2 and for Ar+ and Ar with Ar for laboratory energies from 0.1 eV to 10 keV. Where appropriate, drift velocities and reaction or excitation coefficients are calculated from the cross sections and recommended for use in analyses of swarm experiments and electrical discharges. In the case of N+ in N2, cross sections for momentum transfer, charge transfer, electronic excitation, and electron production are recommended. Drift velocity calculations predict runaway for N+ in N2 for electric field to gas density ratios E/n greater than 4.3×103 Td, where 1 Td (townsend)=10−21 V m2. For N+2 in N2, the cross sections include those for N+ and N+3 formation, electronic excitation, and electron production. Drift velocities and average cross sections are calculated for E/n≥500 Td. In the case of N in N2, only cross sections for momentum transfer are ...
520 citations
TL;DR: In this article, the authors evaluated chemical kinetic data on a number of single step elementary reactions involving small polyatomic molecules which are of importance in propellant combustion, and the results of the first years effort lead to coverage of all pertinent reactions of the following species; H, H 2, H2O, O, OH, OCHO, CHO, CO, NO, NO2, HCN, and N2O.
Abstract: This publication contains evaluated chemical kinetic data on a number of single step elementary reactions involving small polyatomic molecules which are of importance in propellant combustion. The work involves the collection and evaluation of mechanistic and rate information and the use of various methods for the extrapolation and estimation of rate data where information does not exist. The conditions covered range from 500–2500 K and 1017–1022 particles/cm3. The results of the first years effort lead to coverage of all pertinent reactions of the following species; H, H2, H2O, O, OH, OCHO, CHO, CO, NO, NO2, HNO, HNO2, HCN, and N2O.
443 citations
TL;DR: A substantial data base concerning the rate constants for the gas phase reactions of the NO3 radical with organic compounds is now available, with rate constants having been determined using both absolute and relative rate methods as mentioned in this paper.
Abstract: A substantial data base concerning the rate constants for the gas‐phase reactions of the nitrate (NO3) radical with organic compounds is now available, with rate constants having been determined using both absolute and relative rate methods. To date, the majority of these kinetic date have been obtained at room temperature using relative rate techniques utilizing both the reactions of the NO3 radical with other organic compounds and the equilibrium constant for the NO3+NO2⇄N2O5 reactions as the reference reaction. In this article, the literature kinetic and mechanistic data for the gas‐phase reactions of the NO3 radical with organic compounds (through late 1990) have been tabulated, reviewed and evaluated. While this available data base exhibits generally good agreement and self‐consistency, further absolute rate data are needed, preferably as a function of temperature. Most importantly, mechanistic and product data for the reactions of the NO3 radical with organic compounds need to be obtained.
430 citations
TL;DR: In this article, the thermodynamic properties of fluid ethane were investigated using a classical equation for the molar Helmholtz energy, which contains terms multiplied by the exponential of the quadratic and quartic powers of the system density.
Abstract: New correlations for the thermophysical properties of fluid ethane are presented. The correlations are based on a critical evaluation of the available experimental data and have been developed to represent these data over a broad range of the state variables. Estimates for the accuracy of the equations and comparisons with measured properties are given. The reasons for this new study of ethane include significant new and accurate data and improvements in the correlating functions which allow increased accuracy of the correlations—especially in the extended critical region. Short tables of the thermophysical properties of ethane are included. This study complements an earlier study of methane and uses the same correlating equations and format. For the thermodynamic properties, a classical equation for the molar Helmholtz energy, which contains terms multiplied by the exponential of the quadratic and quartic powers of the system density, is used. The resulting equation of state is accurate from about 90 K t...
227 citations
TL;DR: In this paper, rate coefficient measurements for over fifty gas phase bimolecular reactions were evaluated and compared to theoretical calculations, and a recommended rate coefficient expressed as a function of temperature, k(T)=ATnexp(−BT, with probable uncertainty limits, was presented.
Abstract: Rate coefficient measurements for over fifty gas‐phase bimolecular reactions were critically evaluated and compared to theoretical calculations. The results of this work are summarized here in forty‐nine Data Sheets, one sheet for each reaction or set of reactions of a single pair of reagents. The reactions chosen are of interest in propulsion, combustion, and atmospheric chemistry. Each Data Sheet consists of two pages that include a brief resume of the important experimental measurements and theoretical calculations, a graphical presentation of the data, a recommended rate coefficient expressed as a function of temperature, k(T)=ATnexp(−BT), with probable uncertainty limits, a discussion of the basis for the recommendation, an equilibrium constant and a rate coefficient for the reverse reaction where applicable, and pertinent references.
180 citations
TL;DR: In this paper, a critical review of the existing literature on the solubility of CO2 in water from 273 K to the critical temperature of the solvent (647 K) is presented.
Abstract: This critical review covers the existing literature on the solubility of CO2 in water from 273 K to the critical temperature of the solvent (647 K). Results of the evaluation are expressed in the form of fitting equations for the infinite dilution Henry’s constant, k0, as a function of the density of the solvent, and also as an explicit function of the temperature. The pressure effect on the solubility is considered in the formulation. Different equations of state were used for the description of the CO2–H2O vapor phase and the effects on the calculated Henry’s constant values are analyzed. The ‘‘best’’ solubility estimates are presented in smoothed tabular form.
166 citations
TL;DR: In this article, a fit to experimental results for the NaBr+H2O system was obtained from a fit of the thermodynamic properties of this system to the experimental results, which spanned the range of temperature of approximately 260 to 623 K and from the vapor pressure of the solution to 150 MPa.
Abstract: Equations that described the thermodynamic properties of the NaBr+H2O system were obtained from a fit to experimental results for this system. The experimental results included in the fit spanned the range of temperature of approximately 260 to 623 K and the range of pressure from the vapor pressure of the solution to 150 MPa. New equations and/or values for the following properties are given in the present work: 1) the change in chemical potential with respect to temperature and pressure for NaBr(cr), valid from 200 to 900 K, 2) ΔfG0m and ΔfH0m for formation from the elements for NaBr(cr) for 298.15 K and 0.1 MPa, 3) ΔfG0m and ΔfH0m from the elements, as well as S0m and C0p,m, all for 298.15 K, 0.1 MPa for NaBr⋅2H2O(cr), 4) the change in chemical potential for both NaBr and H2O in NaBr(aq) as a function of temperature, pressure, and molality, valid from 260 to 600 K and from the vapor pressure of the solution to 150 MPa.
157 citations
TL;DR: In this article, the Gibbs energy function for aqueous sulfuric acid and its related pure, solid phases have been thermodynamically analyzed and correlated as a function of temperature and composition from pure water to pure acid.
Abstract: Experimental measurements for aqueous sulfuric acid and its related pure, solid phases have been thermodynamically analyzed and correlated as a function of temperature and composition from pure water to pure acid. The pure phases included anhydrous sulfuric acid, five of its hydrates and ice. Experimental data which were used in the correlation included measurements of the enthalpy of dilution, both solution and pure phase heat capacities, electromotive force and solution freezing points. The correlation yielded mutually consistent expressions for the Gibbs energy of each phase and these functions generally reproduce the experimental data to ±0.75 percent. The Gibbs energy functions of the pure solid phases were used to generate tables of their thermodynamic properties from 0 K to the melting points. The Gibbs energy function for aqueous sulfuric acid was used to produce tables of both integral and partial molar solution properties as a function of sulfuric acid mole fraction every 50° from 200 to 350 K.
TL;DR: The energy levels of the krypton atom, in all stages of ionization for which experimental data are available, have been compiled as discussed by the authors, and a value for the ionization energy of each ion, either experimental or theoretical, is included.
Abstract: The energy levels of the krypton atom, in all stages of ionization for which experimental data are available, have been compiled. No data has yet been published for Kr XI through Kr XVIII. For H‐like krypton very accurate calculated level values are compiled. In all, data for 29 spectra are given. Experimental g‐factors are included for Kr I and Kr II. Calculated percentage compositions of levels are given for 12 ions. A value for the ionization energy of each ion, either experimental or theoretical, is included.
TL;DR: In this paper, all significant experimental measurements and theoretical calculations of the spectroscopy and structure of the alkali hydrides NaH, KH, RbH and CsH, and the corresponding alkali deuterides, are identified and reviewed.
Abstract: All significant experimental measurements and theoretical calculations of the spectroscopy and structure of the alkali hydrides NaH, KH, RbH, and CsH, and the corresponding alkali deuterides, are identified and reviewed. Published molecular constant determinations from conventional and laser spectroscopy are evaluated; recommended spectroscopic constants for X 1Σ+ and A 1Σ+ states are tabulated. RKR and hybrid potential energy curves are evaluated; recommended RKR curves for X 1Σ+ and A 1Σ+ states are tabulated. Ground state dissociation energy (De) estimates are evaluated; recommended X 1Σ+ and A 1Σ+ state De and D0 values are tabulated. Accurate electronic structure calculations (Hartree–Fock or better) are listed and described briefly; all excited electron states considered are included. Experimental and theoretical radiative and dipole properties are noted and discussed. Calculations on the positive and negative ions of the four diatomic alkali hydrides are also listed and described briefly.
TL;DR: In this paper, a joint project by the authors has resulted in two new thermodynamic property formulations for oxygen, which are used for the calculation of the property tables presented here, and for comparisons of calculated properties to the experimental data.
Abstract: A joint project by the authors has resulted in two new thermodynamic property formulations for oxygen. The fundamental equation explicit in Helmholtz energy by Schmidt and Wagner has been used for the calculation of the property tables presented here, and for comparisons of calculated properties to the experimental data. The formulation of Stewart and Jacobsen is used in this paper in comparisons of properties calculated by the two formulations. These comparisons provide the basis for independent assessment of the accuracy of the available data and calculated properties. The procedures used in determining the formulations by Wagner and Schmidt, and by Stewart and Jacobsen were published earlier. The fundamental equation is valid for thermodynamic properties of oxygen from the freezing line to 300 K at pressures to 80 MPa. A separate vapor pressure equation and equations for the saturated liquid and saturated vapor densities and the ideal gas heat capacity are included. Functions for calculating internal e...
TL;DR: The Subcommittee for Isotopic Abundance Measurements (SIAM) as discussed by the authors carried out its biennial review of isotopic compositions, as determined by mass spectrometry and other relevant methods.
Abstract: The Subcommittee for Isotopic Abundance Measurements (SIAM) of the IUPAC Commission on Atomic Weights and Isotopic Abundances has carried out its biennial review of isotopic compositions, as determined by mass spectrometry and other relevant methods. The Subcommittee’s critical evaluation of the published literature element by element forms the basis of the Table of Isotopic Compositions of the Elements as Determined by Mass Spectrometry 1989, which is presented in this Report. Atomic Weights calculated from the tabulated isotopic abundances are consistent with Ar(E) values listed in the Table of Standard Atomic Weights 1989.
TL;DR: In this article, all reliable sources of experimental data on the thermodynamic properties of ordinary (light) water and steam have been collected and converted to common temperature, pressure, volume, mass and heat scales.
Abstract: As part of the activities of the International Association for the Properties of Water and Steam, all reliable sources of experimental data on the thermodynamic properties of ordinary (light) water and steam have been collected and converted to common temperature, pressure, volume, mass and heat scales. The data are grouped by state or phase: ideal‐gas properties; sublimation and melting curves; saturation properties; properties of liquid water at ambient pressure; thermodynamic properties of the single‐phase state; and those of metastable states. In each category, a subdivision is made by property. Properties include the volume, enthalpy, heat capacities, sound velocity, internal energy and Joule‐Thomson and related coefficients. The total data collection contains approximately 16 000 data points and covers a century of experimental work at temperatures from 253 to 1273 K and pressures up to 1 GPa. This report characterizes the data and gives the literature references. The actual data collection is avail...
TL;DR: The ATHAS 1980 Data Bank of experimental heat capacities of linear macromolecules is updated in this paper, which includes critically reviewed material on almost 100 polymers and has been computerized so that future updates can be made continuously, and new printouts or computer files will be available from, 1990 on.
Abstract: The prior published ATHAS 1980 Data Bank of experimental heat capacities of linear macromolecules that included critically reviewed material on almost 100 polymers is updated. In addition, the data bank has been computerized so that future updates can be made continuously, and new print‐outs or computer files will be available from the authors from, 1990 on.
TL;DR: In this article, the spectra of magnesium have been analyzed and their classifications have been verified based on the critical evaluations in the compilation of energy levels by Martin and Zalubas, with some updating from the more recent literature.
Abstract: Wavelengths and their classifications are compiled for the spectra of magnesium. Selections of data are based on the critical evaluations in the compilation of energy levels by Martin and Zalubas [1980, J. Phys. Chem. Ref. Data 9, 1–58], with some updating from the more recent literature. All classifications have been verified with predictions made by differencing the energy levels. In addition to the spectra ordered by ionization state, two finding lists are included, one containing Mg I to Mg III and the other Mg IV to Mg XII.
TL;DR: In this paper, the spectral data for the atom and all positive ions of aluminum (Z = 13) were used to calculate the wavelength of the atoms and positive ions, along with the observed values for all classified lines.
Abstract: Wavelengths and their classification have been compiled for the spectra of the atom and all positive ions of aluminum (Z=13). The selections of data are based on the compilations of energy levels by Martin and Zalubas [1979, J. Phys. Chem. Ref. Data 8, 817–864], with some updating from the more recent literature. Wavelengths (or wavenumbers) calculated from the differences of the energy levels are given along with the observed values for all classified lines; these calculated wavelengths should in general be more accurate than the observed values wherever the two values differ significantly. Calculated wavelengths are also given for a number of lines that have not yet been observed, including some important forbidden transitions. The most complete data are given in separate tables for the different spectra. No limitation has been imposed on the wavelength range of the classified lines, except for the omission of x‐ray transitions in the neutral atom. Two finding lists are also included, one for Ali through Aliii and the other for Aliv through Alxiii.
TL;DR: In this article, the structures, frequencies and energies, ideal gas thermodynamic properties and values, have been calculated for cyclopentadiene and several radicals derived from them by ab initio molecular orbital calculations.
Abstract: Structures, frequencies and energies, ideal gas thermodynamic properties and values, have been calculated for cyclopentadiene, cyclopentadienols, and a number of radicals derived from them. The necessary molecular information for these calculaions was found by ab‐initio molecular orbital calculations. The gometries, vibrational frequencies and moments of inertia of 8 species are reported. In order to estimate the accuracy of the computations the molecular parameters were compared with known values reported in the literature whenever those were available.
TL;DR: In this article, a short review of the work on each stage of ionization is included. And Grotrian diagrams are also presented to provide graphical overviews, and the literature has been surveyed to March 1990.
Abstract: Wavelengths, energy levels, level classifications, intensities, and transition probabilities for the copper spectra Cu X to Cu XXIX are compiled. The data are critically evaluated and the best results, in the author’s judgment, are quoted. A short review of the work on each stage of ionization is included. Grotrian diagrams are also presented to provide graphical overviews. The literature has been surveyed to March 1990.
TL;DR: The table of isotopic compositions of the elements 1989 was published as a companion paper to that on Atomic Weights of the Elements 1989 as mentioned in this paper, which includes the table of standard atomic weights, A_r(E), determinations and other cognate data.
Abstract: The biennial review of atomic weight, A_r(E), determinations, and other cognate data has resulted in changes for nickel from 58.69±0.01 to 58.6934±0.0002 and for antimony from 121.75±0.03 to 121.757±0.003 due to new calibrated measurements. Because the measurement of the isotopic composition of mercury has also been improved during the last two years, the Commission was able to reduce the uncertainty of the atomic weight of this element from 200.59±0.03 to 200.59±0.02. Due to the nearly constant isotopic composition of protactinium in nature, where 231Pa is the predominant isotope, the atomic weight of this element was fixed to 231.03588±0.000 02. The Table of Isotopic Compositions of the Elements 1989 will be published as a companion paper to that on Atomic Weights of the Elements 1989. The Table of Standard Atomic Weights Abridged to Five Significant Figures and current data on isotopic compositions of nonterrestrial material are included to benefit users who are more concerned with the length of time d...
TL;DR: Transition temperatures for 367 straight chain 4,4'−alkyl/alkoxyphenylbenzoates (through Nov. 1990) have been compiled and critically evaluated.
Abstract: Transition temperatures for 367 straight chain 4,4’‐alkyl/alkoxyphenylbenzoates (through Nov. 1990) have been compiled and critically evaluated. Information was obtained wherever possible, with the exception of the patent literature, and examined for editorial coherency. Line graphs of the melting and clearing temperatures were plotted as a function of the chain length of either side, while holding constant the other side, and evaluated for consistency, particularly for the persistence of the odd–even alternation in the clearing curve. It became apparent that major breaks in this curve indicated errors in the data which, when corrected, restored the alternating curve. Mesophase identification was reviewed by evaluating bar graphs and block diagrams. Usually, a given phase appeared first in a monotropic form, then in an enantiotropic form, and finally disappeared without reappearing in the series. Further evaluation of the data suggested that a number of phases have been missed. Evaluated transition temperatures are available on 39 dialkyl, 91 alkyl/alkoxy, 100 alkoxy/alkyl, and 137 dialkoxy compounds. Enthalpies for 93 of the esters are also included.