Dry ice and acetone, endothermic?

AI Thread Summary
The discussion centers on the interaction between dry ice and acetone, specifically whether it constitutes an endothermic reaction. Participants clarify that the process is primarily a heat exchange rather than a chemical reaction, with acetone acting as a heat exchange fluid. The dissolution of CO2 in acetone is mentioned as endothermic, contributing to temperature reduction, particularly at around -78°C. However, there is no consensus on the extent of this effect, and participants express frustration over conflicting information and the complexities of thermodynamics. One contributor references a study on gas solubility in hydrocarbons, highlighting the challenges in predicting gas solubility and the thermodynamic changes involved in dissolution. The conversation concludes with a request for resources on thermodynamic equations related to this topic.
_Anthony_
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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.
 
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_Anthony_ said:
endothermic reaction
No. The acetone serves as a heat exchange fluid.
 
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
 
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.
 
_Anthony_ said:
It identifies a Heat of Solution as a contributor to temperature reduction. So the dissolution of CO2 in acetone is endothermic. At a temperature around -78C or so, how much?
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.
 
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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