Calculating Internal Energy of Solid CO2: How to Obtain Thermodynamic Values?

AI Thread Summary
The discussion centers on the challenge of obtaining thermodynamic values for solid CO2, particularly below 212K, as common databases like REFPROP and EES lack this data. CO2 sublimates at approximately 195K at one atmosphere, raising questions about calculating internal energy and entropy in its solid state. Users express confusion over the absence of solid-state properties in available resources, despite having access to specific heat capacity and latent heat data for phase changes. The need for reliable data on solid CO2 thermodynamics is emphasized, highlighting a gap in current thermodynamic databases. Understanding these properties is crucial for accurate thermodynamic analysis involving CO2 in its solid form.
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I am doing a simple thermodynamic analysis. Couldn't get thermodynamic values (such as internal energy, exergy, and so on) from common data base of CO2. I looked it up in REFPROP(By NIST) and EES. None of them have data below 212K. At one atmosphere CO2 sublime at about 195K.
Could anyone explain this to me? How to calculate the internal energy and entropy when CO2 is in solid stae?
Thank you very much!
 
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Thank you very much! I felt that it is kind strange that the properties of solid state are not included.
 
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