Thermodynamics: Cp Variation with Temperature Limit

Thread starter asdf1
Start date Sep 29, 2006
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Thermodynamics

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The variation of heat capacity at constant pressure (Cp) with temperature approaches a limit of approximately 3R due to the principles of equipartition of energy, which states that energy is distributed equally among all degrees of freedom in a system. This limit is particularly relevant for ideal gases where each degree of freedom contributes 1/2 kT to the energy. As temperature increases, the contributions from additional vibrational modes in solids also align with this limit, as described by Dulong-Petit law. The references provided offer further insights into the specific heat of gases and the behavior of solids under thermal conditions. Understanding these concepts is crucial for grasping the thermodynamic properties of various materials.

Sep 29, 2006

asdf1

Why does variation of Cp with temperature tends to a limit of ~3R?

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Sep 29, 2006

Astronuc

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Read these -

Sp. heat of gases - http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/shegas.html - especially the last plate

Equipartition of energy - http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/eqpar.html

Solids - http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/dulong.html

Sep 30, 2006

asdf1

thank you very much!

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