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Dry ice and acetone, endothermic?

  1. Sep 7, 2015 #1
    For decades I've wonder. Is there an endothermic reaction between dry ice and acetone? With ice, salt forces a phase change lowering the temperature but that doesn't seem applicable here.
     
  2. jcsd
  3. Sep 9, 2015 #2

    Bystander

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    No. The acetone serves as a heat exchange fluid.
     
  4. Sep 9, 2015 #3
    So then there's no chemical reaction at all, it's just heat exchange. Than you Bystander, you've confirmed what I thought.

    I guess I put the question in the wrong section. Sorry about that. It was my first post.

    Anthony
     
  5. Sep 10, 2015 #4

    DrDu

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    I would guess it also to be endothermic. After all, the dry ice also dissolves in the acetone. I once made a big mess when pouring some cold acetone still saturated with CO2 into the waste canister.
     
  6. Sep 10, 2015 #5
  7. Sep 10, 2015 #6

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    Zero for temperature difference; generally, evolution of heat for non-reactive dissolution of gases in a liquid phase. Misapplication of the phase rule, treating two phases instead of three, will result in very screwy descriptions of phenomena.
     
  8. Sep 12, 2015 #7
    I've done a good deal of searching since I asked and have found a few morsels of information. With that and the answers here I'm back where I started, no significant consensus and conflicting explanations. I can say I've been reminded how difficult thermodynamics is and how much I've forgotten in the last 50 years.

    I found this little snippet.

    Analele UniversitaGii din Bucureúti – Chimie, Anul XII (serie noua), vol. I-II, pag. 197–202
    Copyright © Analele UniversitaGii din Bucureti

    THE SOLUBILITY OF CO2 AND N2O IN SOME C6 HYDROCARBONS AT HIGH PRESSURES

    I. Gainar

    "A rigorous method for the prediction of gas solubility requires a valid theory of solution but
    such of theory is not available. For a semi empirical description of non-polar systems the
    theory of regular solution can serve as a basis for the correlation of gas solubility"

    For that purpose to consider a gas dissolved isothermally in a liquid far from its critical
    temperature. The dissolution process is accompanied by a change in enthalpy and in
    entropy as in the case when two liquids are mixed. The dissolution of a gas in a liquid is
    accompanied by a large reduction in volume, since the volume of the solute in the
    condensed phase is much smaller then that in the gas phase. This large decrease in volume
    differentiates the dissolution of a gas from the dissolution of a liquid."

    I've gone looking for the various heats of this and that for CO2 on the off chance that I understand. Does anyone know where I can find the relevant thermodynamic equations and maybe an example of how to solve them?

    Anthony
     
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