Fusionfire
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List of endothermic solvation reactions
Hi guys,
Just out of curiosity can anyone find some solvation reactions with lower heats of solvation (on a per gram basis) than some of the following below?
Ammonium nitrate
Molecular mass = 80.05 g/mol
Heat of solvation = 25.69 kJ/mol
Specific heat of solvation = 0.32 kJ/g
Urea
Molecular mass = 60.06 g/mol
Heat of solvation = 13.8 kJ/mol
Specific heat of solvation = 0.23 kJ/g
Potassium chlorate
Molecular mass = 122.55 g/mol
Heat of solvation = 41.38 kJ/mol
Specific heat of solvation = 0.34 kJ/g
I am looking for something that is also reversible by heating to drive the water off so you can "recharge" the system (i.e. the recharge temperature
is not above the decomposition temperature!)
Thanks.
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White Yeti
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One simple endothermic reaction you might be interested in:
CaCl2 + 2NaHCO3 ----> CaCO3 +2NaCl + CO2 +H2O +72.4 kJ/mol
The solvation of CaCl2 as everyone knows is exothermic, so you have to dissolve the CaCl2 first, let it cool and then add the bicarbonate ¡slowly!
"Ja, Kalzium, das ist alles!" -Otto Loewi
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Fusionfire
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Interesting, I didn't know about that reaction. You learn new things every day ![:)](./images/smilies/smile.gif)
CaCl2 (anhydrous) 110.98 g/mol
NaHCO3 84.007 g/mol
Heat of reaction 72.4 kJ/mol
Specific heat of reaction = 0.26 kJ/g
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