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I'm aware of the reaction Calcium chloride has with water vapour and how it can therefore be used as a good and inexpensive drying agent but could that be applicable for solutions?

For example if there is an Ethanol, water mixture which you want to dehydrate could you add Calcium chloride so it forms a complex with the water molecules and then destill the solution to obtain dehydrated ethanol?

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    $\begingroup$ You can do that with some solvents, but not with ethanol. $\endgroup$ – Ivan Neretin Feb 28 at 18:17
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    $\begingroup$ CaCl2 binds with 6 H2O or 4 CH3OH or 3 CH3CH3OH, therefore not applicable for drying ethanol $\endgroup$ – Poutnik Feb 28 at 18:41
  • $\begingroup$ Yes, See: chemistry.stackexchange.com/questions/54878/… $\endgroup$ – Nilay Ghosh Mar 1 at 4:35
  • $\begingroup$ IF you want to get really good drying for small alcohols, the better choice is the right molecular sieve. Some (type 3A sieves for example) have fine-tuned cavities in their structure where water molecules can fit but ethanol, for example, cannot fit. They are the preferred choice of drying agents for several small molecule solvents in the lab. CaCl is a far worse drying agent for those solvents. $\endgroup$ – matt_black Mar 1 at 11:12

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