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Thermodynamic Properties of Thorium Dioxide From 298 to 1,200 °K

As a step in developing new standards of heat capacity applicable up to very high temperatures, the heat content (enthalpy) of thorium dioxide, ThO(2), relative to 273 °K, was accurately measured at ten temperatures from 323 to 1,173 °K. A Bunsen ice calorimeter and a drop method were used to make t...

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Detalles Bibliográficos
Autores principales: Victor, Andrew C., Douglas, Thomas B.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: [Gaithersburg, MD] : U.S. Dept. of Commerce, National Institute of Standards and Technology 1961
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5287267/
https://www.ncbi.nlm.nih.gov/pubmed/32196225
http://dx.doi.org/10.6028/jres.065A.013
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author Victor, Andrew C.
Douglas, Thomas B.
author_facet Victor, Andrew C.
Douglas, Thomas B.
author_sort Victor, Andrew C.
collection PubMed
description As a step in developing new standards of heat capacity applicable up to very high temperatures, the heat content (enthalpy) of thorium dioxide, ThO(2), relative to 273 °K, was accurately measured at ten temperatures from 323 to 1,173 °K. A Bunsen ice calorimeter and a drop method were used to make the measurements on two samples of widely different bulk densities. The corresponding heat-capacity values for the higher density sample are represented within their uncertainty (estimated to be ±0.3 to 0.5%) by the following empirical equation (cal mole(−1) deg(−1) at T °K): [Formula: see text] At 298 °K this equation agrees with previously reported low-temperature measurements made with an adiabatic calorimeter. Values of heat content, heat capacity, entropy, and Gibb’s free energy function are tabulated from 298.15 to 1,200 °K.
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spelling pubmed-52872672020-03-18 Thermodynamic Properties of Thorium Dioxide From 298 to 1,200 °K Victor, Andrew C. Douglas, Thomas B. J Res Natl Bur Stand A Phys Chem Article As a step in developing new standards of heat capacity applicable up to very high temperatures, the heat content (enthalpy) of thorium dioxide, ThO(2), relative to 273 °K, was accurately measured at ten temperatures from 323 to 1,173 °K. A Bunsen ice calorimeter and a drop method were used to make the measurements on two samples of widely different bulk densities. The corresponding heat-capacity values for the higher density sample are represented within their uncertainty (estimated to be ±0.3 to 0.5%) by the following empirical equation (cal mole(−1) deg(−1) at T °K): [Formula: see text] At 298 °K this equation agrees with previously reported low-temperature measurements made with an adiabatic calorimeter. Values of heat content, heat capacity, entropy, and Gibb’s free energy function are tabulated from 298.15 to 1,200 °K. [Gaithersburg, MD] : U.S. Dept. of Commerce, National Institute of Standards and Technology 1961 1961-04-01 /pmc/articles/PMC5287267/ /pubmed/32196225 http://dx.doi.org/10.6028/jres.065A.013 Text en https://creativecommons.org/publicdomain/zero/1.0/ The Journal of Research of the National Bureau of Standards Section A is a publication of the U.S. Government. The papers are in the public domain and are not subject to copyright in the United States. Articles from J Res may contain photographs or illustrations copyrighted by other commercial organizations or individuals that may not be used without obtaining prior approval from the holder of the copyright.
spellingShingle Article
Victor, Andrew C.
Douglas, Thomas B.
Thermodynamic Properties of Thorium Dioxide From 298 to 1,200 °K
title Thermodynamic Properties of Thorium Dioxide From 298 to 1,200 °K
title_full Thermodynamic Properties of Thorium Dioxide From 298 to 1,200 °K
title_fullStr Thermodynamic Properties of Thorium Dioxide From 298 to 1,200 °K
title_full_unstemmed Thermodynamic Properties of Thorium Dioxide From 298 to 1,200 °K
title_short Thermodynamic Properties of Thorium Dioxide From 298 to 1,200 °K
title_sort thermodynamic properties of thorium dioxide from 298 to 1,200 °k
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5287267/
https://www.ncbi.nlm.nih.gov/pubmed/32196225
http://dx.doi.org/10.6028/jres.065A.013
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