Self consistent equations for calculating ideal gas heat capacity, enthalpy and entropy. III. Coal chemicals

It was proved that the enthalpy of saturated vapour as a function of temperature has a maximum for all substances. The dependence of the entropy of saturated vapour on temperature can be monotonous, has a minimum and a maximum, or has only a maximum. The thermodynamic relations were derived for the existence of the extremes which enable their computation from the knowledge of dependence of the ideal-gas heat capacity on temperature and an equation of state. A method based on the theorem of corresponding states was proposed for estimating the extremes, and its results were compared with literature data. The agreement between the literature and estimated temperatures corresponding to the extremes is very good. The procedure proposed can serve for giving precision to the H-p and T-S diagrams commonly used in applied thermodynamics.

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Ideal–Gas Thermochemical Properties for Alkanolamine and Related Species Involved in Carbon Capture Applications

10.26434/chemrxiv.12743552 ◽

2020 ◽

Author(s):

Nayyereh hatefi ◽

William Smith

Keyword(s):

Heat Capacity ◽

Electronic Structure ◽

Co2 Capture ◽

Carbon Capture ◽

Ideal Gas ◽

Thermochemical Properties ◽

Temperature Range ◽

Comparison Results ◽

Electronic Structure Methods ◽

Protonated Forms

<div>Ideal{gas thermochemical properties (enthalpy, entropy, Gibbs energy, and heat capacity, Cp) of 49 alkanolamines potentially suitable for CO2 capture applications and their carbamate and protonated forms were calculated using two high{order electronic structure methods, G4 and G3B3 (or G3//B3LYP). We also calculate for comparison results from the commonly used B3LYP/aug-cc-pVTZ method. This data is useful for the construction of molecular{based thermodynamic models of CO2 capture processes involving these species. The Cp data for each species over the temperature range 200 K{1500 K is presented as functions of temperature in the form of NASA seven-term polynomial expressions, permitting the set of thermochemical properties to be calculated over this temperature range. The accuracy of the G3B3 and G4 results is estimated to be 1 kcal/mol and the B3LYP/aug-cc-pVTZ results are of nferior quality..</div>

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Heat capacity, enthalpy and entropy of Sr14Co11O33 and Sr6Co5O15

Thermochimica Acta ◽

10.1016/j.tca.2013.10.031 ◽

2014 ◽

Vol 575 ◽

pp. 167-172 ◽

Cited By ~ 13

Author(s):

Ondřej Jankovský ◽

David Sedmidubský ◽

Zdeněk Sofer ◽

Jindřich Leitner ◽

Květoslav Růžička ◽

...

Keyword(s):

Heat Capacity ◽

Enthalpy And Entropy

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Temperature dependence of the specific heat and thermodynamic functions AК1М2 alloy, doped strontium

Izvestiya Vysshikh Uchebnykh Zavedenii Materialy Elektronnoi Tekhniki = Materials of Electronics Engineering ◽

10.17073/1609-3577-2018-1-35-42 ◽

2019 ◽

Vol 21 (1) ◽

pp. 35-42 ◽

Cited By ~ 2

Author(s):

I. N. Ganiev ◽

S. E. Otajonov ◽

N. F. Ibrohimov ◽

M. Mahmudov

Keyword(s):

Heat Capacity ◽

Gibbs Energy ◽

Specific Heat ◽

Temperature Dependence ◽

Specific Heat Capacity ◽

Thermodynamic Functions ◽

Inverse Relationship ◽

Alloying Element ◽

Enthalpy And Entropy ◽

Increasing Temperature

In the heat «cooling» investigated the temperature dependence of the specific heat capacity and thermodynamic functions doped strontium alloy AK1М2 in the range 298,15—900 K. Mathematical models are obtained that describe the change in these properties of alloys in the temperature range 298.15—900 K, as well as on the concentration of the doping component. It was found that with increasing temperature, specific heat capacity, enthalpy and entropy alloys increase, and the concentration up to 0.5 wt.% of the alloying element decreases. Gibbs energy values have an inverse relationship, i.e., temperature — decreases the content of alloying component — is up to 0.5 wt.% growing.

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