4 replies to this topic

[Fuentes487]

Hi

I have some questions regarding a exothermic reaction of a mixture of 874 kg of 95% Ethanol and 4459 kg of cold water (cWFI). How exothermic is this reaction if the initial temperatures of cWFI: 5 degress celsius amd Ethanol:-19 degrees celsius. what is the amount of energy released due to the reaction and whats the final temperature of the mixture?

 

Also another question, the tabulated value Excess enthalpy/molar heat of solution is it only to be multiplicated with the total amount of moles ethanol? or does also includes the total amount of moles water?

 

Attached excel spreadsheet are some examples of the calculations

 

Thanks in advance for the help

 

Cristopher

Attached Files

•  Cooling BUF.xlsx   36.25KB   12 downloads

[latexman]

From a practical standpoint, there is no exotheric reaction between liquid ethanol at -19^oC and liquid water at 5^oC. If there is a heat of mixing between ethanol and water at these conditions, it is trivial. I doubt you can even find published data on the heat of mixing between ethanol and water at these conditions, because it is so trivial.

Are you playing tricks on us, or has someone played a trick on you? It was Halloween yesterday!

[Fuentes487]

@Latexman, I really thought the reaction betwen water and ethanol would be a little exothermic, and increase the temperature a bit (the reaction itself with molecules of water and ethanol) Besides the heat of mixing of the the two fluids with different initial temperatures as mentioned, I have a final T at approx 3,5 degrees. Just doing a sanity check:)

[breizh]

Hi,

http://www.ddbst.com...hanol;Water.php

Breizh

[latexman]

Excellent find, breizh!

Fuentes487, what’s the temperature deviation from the ideal solution calculation of your mixture? Maybe I’ll learn something. My guess is it is less than 1-2 degrees C.