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Earl M Woolley - One of the best experts on this subject based on the ideXlab platform.
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apparent Molar volumes and apparent Molar Heat capacities of aqueous magnesium nitrate strontium nitrate and manganese nitrate at temperatures from 278 15 k to 393 15 k and at the pressure 0 35 mpa
The Journal of Chemical Thermodynamics, 2007Co-Authors: J S Jones, S P Ziemer, B R Brown, Earl M WoolleyAbstract:Abstract Apparent Molar volumes Vϕ and apparent Molar Heat capacities Cp,ϕ were determined at the pressure 0.35 MPa for aqueous solutions of magnesium nitrate Mg(NO3)2 at molalities m = (0.02 to 1.0) mol · kg−1, strontium nitrate Sr(NO3)2 at m = (0.05 to 3.0) mol · kg−1, and manganese nitrate Mn(NO3)2 at m = (0.01 to 0.5) mol · kg−1. Our Vϕ values were calculated from solution densities obtained at T = (278.15 to 368.15) K using a vibrating-tube densimeter, and our Cp,ϕ values were calculated from solution Heat capacities obtained at T = (278.15 to 393.15) K using a twin fixed-cell, differential, temperature-scanning calorimeter. Empirical functions of m and T were fitted to our results, and standard state partial Molar volumes and Heat capacities were obtained over the ranges of T investigated.
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apparent Molar volumes and apparent Molar Heat capacities of aqueous adonitol dulcitol glycerol meso erythritol myo inositol d sorbitol and xylitol at temperatures from 278 15 to 368 15 k and at the pressure 0 35 mpa
The Journal of Chemical Thermodynamics, 2007Co-Authors: M B Blodgett, S P Ziemer, Travis L Niederhauser, B R Brown, Earl M WoolleyAbstract:Abstract Apparent Molar volumes Vϕ were determined for aqueous adonitol, dulcitol, glycerol, meso-erythritol, myo-inositol, d -sorbitol, and xylitol at temperatures from (278.15 to 368.15) K and at the pressure 0.35 MPa, and apparent Molar Heat capacities Cp,ϕ of the same solutions were determined at temperatures from (278.15 to 363.15) K at the same pressure. Molalities m/(mol · kg−1) of the solutions were in the range (0.02 ⩽ m ⩽ 3.2) for adonitol, (0.02 ⩽ m ⩽ 0.15) for dulcitol, (0.02 ⩽ m ⩽ 5.0) for glycerol, (0.02 ⩽ m ⩽ 3.0) for meso-erythritol, (0.02 ⩽ m ⩽ 0.5) for myo-inositol, (0.02 ⩽ m ⩽ 2.0) for d -sorbitol, and (0.02 ⩽ m ⩽ 2.7) for xylitol. A vibrating tube densimeter was used to obtain solution densities and a fixed-cell temperature scanning calorimeter was used to obtain Heat capacities. Values of Vϕ and Cp,ϕ for these sugar alcohols are discussed relative to one another and compared to values from the literature, where available.
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apparent Molar volumes and apparent Molar Heat capacities of aqueous urea 1 1 dimethylurea and n n dimethylurea at temperatures from 278 15 to 348 15 k and at the pressure 0 35 mpa
The Journal of Chemical Thermodynamics, 2006Co-Authors: B R Brown, S P Ziemer, Travis L Niederhauser, M E Gould, Earl M WoolleyAbstract:Abstract Apparent Molar volumes V ϕ and apparent Molar Heat capacities C p, ϕ were determined for aqueous solutions of urea, 1,1-dimethylurea, and N , N ′-dimethylurea. Measurements were made at molalities m = (0.02 to 6.0) mol · kg −1 for urea, at m = (0.01 to 1.6) mol · kg −1 for 1,1-dimethylurea, and at m = (0.01 to 8.0) mol · kg −1 for N , N ′-dimethylurea. Experimental temperatures ranged from (278.15 to 318.15) K for both urea and 1,1-dimethylurea, and from (278.15 to 348.15) K for N , N ′-dimethylurea. All measurements were conducted at the pressure p = 0.35 MPa. Density measurements obtained with a vibrating-tube densimeter were used to calculate V ϕ values. Heat capacity measurements obtained with a twin fixed-cell differential temperature-scanning calorimeter were used to calculate C p, ϕ values. Functions of m and T were fitted to the results and were compared with the literature values. The “structure making/structure breaking” aspects of urea in water are discussed. Comparisons are made between the different urea compounds, and the effects of the methyl-group additions are outlined.
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thermodynamics of proton dissociation from aqueous bicarbonate apparent Molar volumes and apparent Molar Heat capacities of potassium carbonate and potassium bicarbonate at t 278 15 to 393 15 k and at the pressure 0 35 mpa
The Journal of Chemical Thermodynamics, 2004Co-Authors: E C Sorenson, Earl M WoolleyAbstract:Abstract We have determined the apparent Molar volumes V φ and apparent Molar Heat capacities C p, φ of aqueous potassium carbonate and potassium bicarbonate solutions in the ranges (0.014⩽ m /(mol · kg −1 )⩽0.51) and (278.15⩽ T /K⩽393.15) at the pressure p =0.35 MPa. Corrections for speciation due to hydrolysis and disproportionation in solution were applied using Young's rule, and semi-empirical equations representing ( V φ , m , T ) and ( C p, φ , m , T ) for the species {2K + , CO 3 2− (aq)} and {K + , HCO 3 − (aq)} were fitted to the experimental results. We have used these equations to estimate the change in volume Δ r V m , change in Heat capacity Δ r C p,m , enthalpy change Δ r H m , entropy change Δ r S m , and equilibrium molality quotient pQ for the second proton dissociation reaction from aqueous carbonic acid.
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apparent Molar volumes and apparent Molar Heat capacities of aqueous barium nitrate at temperatures from 278 15 to 393 15 k and at the pressure 0 35 mpa
The Journal of Chemical Thermodynamics, 2004Co-Authors: Travis L Niederhauser, Earl M WoolleyAbstract:Abstract Apparent Molar volumes Vφ and apparent Molar Heat capacities Cp,φ were determined for aqueous solutions of barium nitrate Ba(NO3)2 at molalities m=(0.0025 to 0.2) mol · kg−1, at T=(278.15 to 393.15) K, and at the pressure 0.35 MPa. Our Vφ values were calculated from densities obtained using a vibrating-tube densimeter, and our Cp,φ values were obtained using a twin fixed-cell, power-compensation, differential-output, temperature-scanning calorimeter. Our results were fitted to functions of m and T and compared with values from the literature.
Rhoda B Leron - One of the best experts on this subject based on the ideXlab platform.
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Molar Heat capacities of diethylenetriamine and 3 methylamino propylamine their aqueous binaries and aqueous ternaries with piperazine
Thermochimica Acta, 2014Co-Authors: Shuyu Lin, Rhoda B LeronAbstract:Abstract The Molar Heat capacities, CP, of two new potential polyamine CO2 absorbents: diethylenetriamine (DETA) and 3-(methylamino)propylamine (MAPA), their aqueous binaries, and aqueous ternaries containing piperazine (PZ) were measured at temperatures from 303.15 K to 353.15 K. Measurements were performed at atmospheric pressure by Heat flow differential scanning calorimetry. A linear relation suitably represented the temperature dependence of the CP of pure amines. The excess Molar Heat capacities, C P E , of the binary solutions were investigated, and the data were represented as function of temperature and composition using a Redlich–Kister-type equation. The CP of the ternary mixtures was correlated with temperature and amine concentration using the Sohnel and Novotny equation. Results showed that the calculated data agree very well with the experimental CP values at average absolute deviation values of 0.13%, 0.20, and 0.06 for the pure, binary, and ternary systems, respectively.
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Molar Heat capacities and electrical conductivities of two ammonium based deep eutectic solvents and their aqueous solutions
Thermochimica Acta, 2013Co-Authors: Kathrina R Siongco, Rhoda B Leron, Alvin R CaparangaAbstract:Abstract In this work, we reported new experimental data on the Molar Heat capacity, CP, and electrical conductivity, κ, of two ammonium-based deep eutectic solvents (DESs), N,N-diethylethanolammonium chloride-glycerol and N,N-diethylethanolammonium chloride-ethylene glycol, and their aqueous solutions. Heat capacity measurements were performed, using a Heat flow differential scanning calorimeter, at atmospheric pressure at temperatures from 303.15 to 353.15 K. The CP values were found to increase with temperature. Excess Molar Heat capacities, CPE, of the aqueous DES solutions were determined, and represented as function of temperature and DES mole fraction using a Redlich–Kister-type equation. Electrical conductivities were measured from 298.15 to 343.15 K, and a modified form of the Arrhenius equation was used to correlate the obtained κ data with temperature and DES mole fraction. The applied correlations successfully represented the experimental CP and κ data as function of temperature and composition at low average absolute deviations of 0.1 and 1.3%, respectively.
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Molar Heat capacity of several aqueous solutions of n tris hydroxymethyl methyl 3 amino propanesulfonic acid taps glycol
Thermochimica Acta, 2012Co-Authors: Alvin R Caparanga, Rhoda B LeronAbstract:Abstract The Molar Heat capacity ( C p ) of a potential solvent system for CO 2 absorption, containing water, glycol and n -[tris(hydroxymethyl)methyl-3-amino]propanesulfonic acid (TAPS), was measured at 30–80 °C and different concentrations via differential scanning calorimetry. Each of the glycols – diethylene glycol (DEG), triethylene glycol (TEG), tetraethylene glycol (T 4 EG), propylene glycol (PG), dipropylene glycol (DPG) and tripropylene glycol (TPG) – was mixed with TAPS + H 2 O to form ternary systems consisting of a fixed amount of the glycol (40 mass%) and variable TAPS/H 2 O proportions (4–16 mass% TAPS or 56–44% H 2 O). An extended Redlich–Kister -type equation was used to correlate Heat capacity with concentration and temperature; the average absolute deviation (AAD) of the 198 data points from the corresponding values predicted by the correlation was 0.04%. The new set Heat capacity data or the correlation, reported for the ternary system considered, can be used with high degree of accuracy in process design calculations for systems that will utilize these solvent systems.
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Molar Heat capacities of choline chloride based deep eutectic solvents and their binary mixtures with water
Thermochimica Acta, 2012Co-Authors: Rhoda B LeronAbstract:Abstract In this study, the Molar Heat capacities, CP, of three choline chloride-based deep eutectic solvents (DESs); Reline, Ethaline and Glyceline, and their binary mixtures with water were determined. Using a Heat flow differential scanning calorimeter, the Heat capacities were measured at standard pressure from (303.2 to 353.2) K and over the complete range of composition. Results showed that the Molar Heat capacity increased with increasing temperature and, for the binary systems, with increasing DES concentration. The temperature-dependence of the pure DESs were successfully represented by a second-order empirical correlation with an AAD% of 0.05. The excess Molar Heat capacities, C P E , of the binary mixtures also determined and found generally negative over the whole composition range while exhibiting negative temperature dependence. The C P E values were fitted to a Redlich–Kister type equation to correlate them to the temperature and DES mole fraction and the Molar Heat capacities of the binary mixtures were predicted. The applied models successfully correlated the experimental CP data as functions of both temperature and composition.
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Molar Heat capacities of choline chloride based deep eutectic solvents and their binary mixtures with water
Thermochimica Acta, 2012Co-Authors: Rhoda B Leron, Menghui LiAbstract:Abstract In this study, the Molar Heat capacities, CP, of three choline chloride-based deep eutectic solvents (DESs); Reline, Ethaline and Glyceline, and their binary mixtures with water were determined. Using a Heat flow differential scanning calorimeter, the Heat capacities were measured at standard pressure from (303.2 to 353.2) K and over the complete range of composition. Results showed that the Molar Heat capacity increased with increasing temperature and, for the binary systems, with increasing DES concentration. The temperature-dependence of the pure DESs were successfully represented by a second-order empirical correlation with an AAD% of 0.05. The excess Molar Heat capacities, C P E , of the binary mixtures also determined and found generally negative over the whole composition range while exhibiting negative temperature dependence. The C P E values were fitted to a Redlich–Kister type equation to correlate them to the temperature and DES mole fraction and the Molar Heat capacities of the binary mixtures were predicted. The applied models successfully correlated the experimental CP data as functions of both temperature and composition.
Xiangyang Liu - One of the best experts on this subject based on the ideXlab platform.
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experimental study on isobaric Molar Heat capacities of a deep eutectic solvent choline chloride ethylene glycol
Journal of Chemical & Engineering Data, 2020Co-Authors: Chenyang Zhu, Sa Xue, Rana Ikram, Xiangyang LiuAbstract:In this study, a flow calorimeter is used to measure the isobaric Molar Heat capacities (Cp) of one deep eutectic solvent (DES) containing choline chloride and ethylene glycol at different Molar ratios. The experiment is performed at temperatures from 313 to 343 K and pressures up to 25 MPa, while the expanded uncertainties of temperature, pressure, Molar fraction, and Cp are estimated to be lower than 0.02 K, 5.0 kPa, 1.4 × 10–4, and 1.28%, respectively. The results show that Cp change linearly with temperature, while it is almost constant with a variety of pressure. A quadratic relation between Cp and Molar fraction of ethylene glycol is observed, which shows a decreasing tendency with the increase of Molar fraction. A correlation for the Cp of the chosen DES and pure ethylene glycol is proposed for a better application of the data.
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isobaric Molar Heat capacities measurement of binary mixtures containing ethyl laurate and ethanol at high pressures
Journal of Molecular Liquids, 2019Co-Authors: Chenyang Zhu, Feng Yang, Xiangyang LiuAbstract:Abstract A flow calorimeter was used to determine the isobaric Molar Heat capacities of mixtures containing ethyl laurate and ethanol at temperatures from 313.15 K to 343.15 K and pressures up to 25 MPa. The experimental system was verified by measuring the isobaric Molar Heat capacities of pure ethanol at different temperatures and pressures, and the relative expanded uncertainty of the measurement results was estimated to be lower than 1.45%. Then, the excess Molar Heat capacity which characterizes the deviation of the mixtures from the ideality was evaluated. Moreover, the excess Molar Heat capacities were analyzed, and a Redlich-Kister type correlation was presented for fitting. After that, absorbing the Redlich-Kister correlation, a new correlation for the isobaric Molar Heat capacities of mixtures was proposed, and the calculated results were compared with the experimental data. At last, to reduce the parameters used in calculation process, another correlation for the isobaric Molar Heat capacities of mixtures was also proposed, and a comparison of two correlations was implemented.
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experimental and correlational study of isobaric Molar Heat capacities of fatty acid esters ethyl nonanoate and ethyl dodecanoate
Fluid Phase Equilibria, 2019Co-Authors: Xiangyang Liu, Chenyang Zhu, Feng YangAbstract:Abstract An experimental study on the isobaric Molar Heat capacities of ethyl nonanoate and ethyl dodecanoate was performed at temperatures between 303 K and 393 K and at pressures between 0.1 MPa and 25.2 MPa. An increase of isobaric Molar Heat capacity with temperature increase was observed, and temperature was found to have a greater effect on isobaric Molar Heat capacity than pressure. Then the isobaric Molar Heat capacity data of 18 saturated fatty acid methyl and ethyl esters in literature were selected, to get a general correlation for the isobaric Molar Heat capacity of saturated fatty acid alkyl esters. The average absolute relative deviation and the maximum deviation of the present correlation from experimental data are lower than 0.70% and 3.82%, respectively. At last, to test the predictive ability of the proposed correlation, the Heat capacities of ethyl nonanoate and ethyl dodecanoate were calculated. The average absolute relative deviation and the maximum deviation from our experimental results are 0.88% and 2.10%, respectively.
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Isobaric Molar Heat Capacity of Ethyl Octanoate and Ethyl Decanoate at Pressures up to 24 MPa
Journal of Chemical & Engineering Data, 2018Co-Authors: Chenyang Zhu, Feng Yang, Xiangyang LiuAbstract:The isobaric Molar Heat capacities of ethyl octanoate and ethyl decanoate were determined at T = 294–354 K and p = 0.1–24 MPa. The measurements were conducted by a flow calorimeter. The measured results were in good agreements with several available experimental data at atmosphere pressure and the calculated results at high pressure in literatures. Furthermore, a fitting equation was presented to calculate the Cp of ethyl octanoate and ethyl decanoate. The maximum absolute relative deviations between experimental results and calculated data are lower than 0.4%.
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isobaric Molar Heat capacities of binary mixtures containing methyl caprate and methyl laurate at pressures up to 16 2 mpa
Thermochimica Acta, 2017Co-Authors: Xiangyang Liu, Chenyang Zhu, Wei Dong, Tansu Shang, Weiping YangAbstract:Abstract In this work, the isobaric Molar Heat capacities of methyl caprate, methyl laurate and their mixtures at temperatures from 313 K to 335 K and at pressures up to 16.2 MPa were measured using a flow calorimeter. The isobaric Molar Heat capacities of these mixtures were observed to increase as the temperature and the concentration of methyl laurate rise, while they increase as the pressure falls. The excess Molar Heat capacities were calculated using the experimental Heat capacity data, which are positive and very small compared to the isobaric Molar Heat capacities. A correlation was proposed for the isobaric Molar Heat capacities of the methyl caprate and methyl laurate mixtures with the maximum deviation of 1.8%.
Chenyang Zhu - One of the best experts on this subject based on the ideXlab platform.
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experimental study on isobaric Molar Heat capacities of a deep eutectic solvent choline chloride ethylene glycol
Journal of Chemical & Engineering Data, 2020Co-Authors: Chenyang Zhu, Sa Xue, Rana Ikram, Xiangyang LiuAbstract:In this study, a flow calorimeter is used to measure the isobaric Molar Heat capacities (Cp) of one deep eutectic solvent (DES) containing choline chloride and ethylene glycol at different Molar ratios. The experiment is performed at temperatures from 313 to 343 K and pressures up to 25 MPa, while the expanded uncertainties of temperature, pressure, Molar fraction, and Cp are estimated to be lower than 0.02 K, 5.0 kPa, 1.4 × 10–4, and 1.28%, respectively. The results show that Cp change linearly with temperature, while it is almost constant with a variety of pressure. A quadratic relation between Cp and Molar fraction of ethylene glycol is observed, which shows a decreasing tendency with the increase of Molar fraction. A correlation for the Cp of the chosen DES and pure ethylene glycol is proposed for a better application of the data.
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isobaric Molar Heat capacities measurement of binary mixtures containing ethyl laurate and ethanol at high pressures
Journal of Molecular Liquids, 2019Co-Authors: Chenyang Zhu, Feng Yang, Xiangyang LiuAbstract:Abstract A flow calorimeter was used to determine the isobaric Molar Heat capacities of mixtures containing ethyl laurate and ethanol at temperatures from 313.15 K to 343.15 K and pressures up to 25 MPa. The experimental system was verified by measuring the isobaric Molar Heat capacities of pure ethanol at different temperatures and pressures, and the relative expanded uncertainty of the measurement results was estimated to be lower than 1.45%. Then, the excess Molar Heat capacity which characterizes the deviation of the mixtures from the ideality was evaluated. Moreover, the excess Molar Heat capacities were analyzed, and a Redlich-Kister type correlation was presented for fitting. After that, absorbing the Redlich-Kister correlation, a new correlation for the isobaric Molar Heat capacities of mixtures was proposed, and the calculated results were compared with the experimental data. At last, to reduce the parameters used in calculation process, another correlation for the isobaric Molar Heat capacities of mixtures was also proposed, and a comparison of two correlations was implemented.
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experimental and correlational study of isobaric Molar Heat capacities of fatty acid esters ethyl nonanoate and ethyl dodecanoate
Fluid Phase Equilibria, 2019Co-Authors: Xiangyang Liu, Chenyang Zhu, Feng YangAbstract:Abstract An experimental study on the isobaric Molar Heat capacities of ethyl nonanoate and ethyl dodecanoate was performed at temperatures between 303 K and 393 K and at pressures between 0.1 MPa and 25.2 MPa. An increase of isobaric Molar Heat capacity with temperature increase was observed, and temperature was found to have a greater effect on isobaric Molar Heat capacity than pressure. Then the isobaric Molar Heat capacity data of 18 saturated fatty acid methyl and ethyl esters in literature were selected, to get a general correlation for the isobaric Molar Heat capacity of saturated fatty acid alkyl esters. The average absolute relative deviation and the maximum deviation of the present correlation from experimental data are lower than 0.70% and 3.82%, respectively. At last, to test the predictive ability of the proposed correlation, the Heat capacities of ethyl nonanoate and ethyl dodecanoate were calculated. The average absolute relative deviation and the maximum deviation from our experimental results are 0.88% and 2.10%, respectively.
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Isobaric Molar Heat Capacity of Ethyl Octanoate and Ethyl Decanoate at Pressures up to 24 MPa
Journal of Chemical & Engineering Data, 2018Co-Authors: Chenyang Zhu, Feng Yang, Xiangyang LiuAbstract:The isobaric Molar Heat capacities of ethyl octanoate and ethyl decanoate were determined at T = 294–354 K and p = 0.1–24 MPa. The measurements were conducted by a flow calorimeter. The measured results were in good agreements with several available experimental data at atmosphere pressure and the calculated results at high pressure in literatures. Furthermore, a fitting equation was presented to calculate the Cp of ethyl octanoate and ethyl decanoate. The maximum absolute relative deviations between experimental results and calculated data are lower than 0.4%.
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isobaric Molar Heat capacities of binary mixtures containing methyl caprate and methyl laurate at pressures up to 16 2 mpa
Thermochimica Acta, 2017Co-Authors: Xiangyang Liu, Chenyang Zhu, Wei Dong, Tansu Shang, Weiping YangAbstract:Abstract In this work, the isobaric Molar Heat capacities of methyl caprate, methyl laurate and their mixtures at temperatures from 313 K to 335 K and at pressures up to 16.2 MPa were measured using a flow calorimeter. The isobaric Molar Heat capacities of these mixtures were observed to increase as the temperature and the concentration of methyl laurate rise, while they increase as the pressure falls. The excess Molar Heat capacities were calculated using the experimental Heat capacity data, which are positive and very small compared to the isobaric Molar Heat capacities. A correlation was proposed for the isobaric Molar Heat capacities of the methyl caprate and methyl laurate mixtures with the maximum deviation of 1.8%.
Zhicheng Tan - One of the best experts on this subject based on the ideXlab platform.
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low temperature Molar Heat capacities thermodynamic properties and crystal structure of cu c 3 n 2 h 4 4 clo 4 2
Journal of Thermal Analysis and Calorimetry, 2018Co-Authors: Lu Pan, Xiaohan Gao, Zhicheng TanAbstract:A complex of copper perchlorate coordinated with imidazole Cu(C3N2H4)4(ClO4)2 was synthesized and characterized by X-ray single-crystal diffraction. The complex is centrosymmetric in the monoclinic P2(1)/c space group. The low-temperature Molar Heat capacities and thermodynamic properties of the complex were studied with adiabatic calorimetry (AC). The thermodynamic functions [H T–H 298.15] and [S T–S 298.15] were derived in the temperature range from 80 to 370 K with temperature interval of 5 K. Thermal decomposition behavior of the complex in nitrogen atmosphere was studied by thermogravimetric (TG) analysis and differential scanning calorimetry (DSC). The mechanism of the decomposition was deduced to be the breaking up the two Cl–O bonds of the Cl–O–Cu and the Cu–N bonds of the imidazole rings in succession.
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low temperature Molar Heat capacities and thermodynamic properties of a new rare earth complex er 2 μ 2 gly 6 h 2 o 4 na 2 clo 4 8 h 2 o 2 4h 2 o
Journal of Thermal Analysis and Calorimetry, 2016Co-Authors: Guanhua Luo, Xiaohan Gao, Lu Pan, Zhicheng TanAbstract:A hydrous complex of erbium coordinated with glycine sodium perchloric acid, Er2(μ 2-Gly)6(H2O)4·Na2(ClO4)8(H2O)2·4H2O (Gly = glycine), was synthesized firstly and characterized by X-ray single-crystal diffraction. The complex crystallizes centrosymmetrically in the triclinic P-1 space group [a = 9.2959 (5), b = 12.1756 (7) A, c = 13.9928 (7) A, V = 1367.67 (13) A3, Z = 1]. The low-temperature Molar Heat capacities and thermodynamic properties of the complex were studied with adiabatic calorimetry. The thermodynamic functions, [H T–H 298.15] and [S T–S 298.15], were derived in the temperature range from 80 to 370 K with a temperature interval of 5 K. Thermal decomposition behavior of the complex in nitrogen atmosphere was studied by thermogravimetric analysis and differential scanning calorimetry.
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low temperature Heat capacities and standard Molar enthalpy of formation of the solid state coordination compound trans cu ala 2 s ala l α alanine
Thermochimica Acta, 2008Co-Authors: Jingtao Chen, Zhicheng TanAbstract:Low-temperature Heat capacities of the solid coordination compound trans-Cu(Gly)2·H2O(s) were measured by a precision automated adiabatic calorimeter over the temperature range from T = 78 K to T = 381 K. The initial dehydration temperature of the coordination compound was determined to be TD = 329.50 K, by analysis of the Heat-capacity curve. The experimental values of the Molar Heat capacities in the temperature region of 78−328 K were fitted to a polynomial equation of Heat capacities (Cp,m) with the reduced temperatures (X), [X = f(T)], by a least-squares method. The smoothed Molar Heat capacities and thermodynamic functions of the complex trans-Cu(Gly)2·H2O(s) were calculated based on the fitted polynomial. The smoothed values of the Molar Heat capacities and fundamental thermodynamic functions of the sample relative to the standard reference temperature 298.15 K were tabulated with an interval of 5 K. Enthalpies of dissolution of {Cu(Ac)2·H2O(s) + 2Gly(s)} [ΔsHmϑ (1)] and HAc(l) [ΔsHmϑ (2)] in 100.0...
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low temperature Heat capacities and standard Molar enthalpy of formation of chromium nicotinate cr c6h4no2 3 s
Journal of Chemical & Engineering Data, 2008Co-Authors: Weiwei Yang, Quan Shi, Yuxia Kong, Zhicheng TanAbstract:Low-temperature Heat capacities of the solid coordination compound Cr(C6H4NO2)3(s) have been measured by a precision automated adiabatic calorimeter over the temperature range T = 78 K to T = 391 K. The experimental values of the Molar Heat capacities in the temperature region were fitted to a polynomial equation of Heat capacities (Cp,m) with the reduced temperatures (X), [X = f(T)], by a least-squares method. The smoothed Molar Heat capacities and thermodynamic functions of the complex Cr(C6H4NO2)3(s) were calculated based on the fitted polynomial. The smoothed values of the Molar Heat capacities and fundamental thermodynamic functions of the sample relative to the standard reference temperature 298.15 K are tabulated with an interval of 5 K. Enthalpies of dissolution of {3C6H5NO2(s)} [ΔdHm⊖(1)] and Cr(C6H4NO2)3(s) [ΔdHm⊖(3)] in 100.00 mL of 0.1 mol·dm−3 HCl and {Cr(OH)3(s)} [ΔdHm⊖(2)] in 100.00 mL of 0.1 mol·dm−3 HCl solution containing certain amounts of nicotinic acid (named as solution A1) at T = 29...
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Molar Heat capacity and thermodynamic properties of 4 methyl 4 cyclohexene 1 2 dicarboxylic anhydride c9h10o3
Journal of Chemical & Engineering Data, 2005Co-Authors: Zhicheng Tan, Quan Shi, Hongtao Zhang, Lixian Sun, Tao ZhangAbstract:The Molar Heat capacity Cp,m of 4-methyl-4-cyclohexene-1,2-dicarboxylic anhydride was measured over the temperature range from T = 80 K to T = 361 K with a small-sample automated adiabatic calorimeter. The melting point Tm and the Molar enthalpy ΔfusHm and entropy ΔfusSm of fusion for the compound were determined to be (335.54±0.41) K, (17.67±0.04) kJ·mol-1, and (52.65±0.04) J·K-1·mol-1, respectively. Thermodynamic functions [HT − H298.15] and [ST − S298.15] were derived in the temperature range from T = 80 K to T = 361 K with a temperature interval of 5 K. The purity of the sample in mole fraction used in the adiabatic calorimetry study was determined to be 0.9940 by using the fractional melting technique. The thermal stability of the compound was investigated by differential scanning calorimetry (DSC) and a thermogravimetric (TG) technique, and the process of the mass loss of the sample was due to evaporation instead of thermal decomposition.
