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Drying agent vs Dehydrating agent

Hi, quick question: What's the difference between a dehydrating agent and a drying agent?
Original post by ChrisBee
Hi, quick question: What's the difference between a dehydrating agent and a drying agent?


Not certain about this, but the uses of these that I have come across is:

drying agent simply mops up water in the reaction vessel. e.g. removing water from a non-aqueous solvent.

dehydrating agent is used to remove water from the molecule
Reply 2
Original post by JMaydom
Not certain about this, but the uses of these that I have come across is:

drying agent simply mops up water in the reaction vessel. e.g. removing water from a non-aqueous solvent.

dehydrating agent is used to remove water from the molecule

Thanks for the response, does anyone else agree?
Reply 3
Original post by ChrisBee
Thanks for the response, does anyone else agree?


I agree
Reply 4
Original post by ChrisBee
Thanks for the response, does anyone else agree?


I would concur with what he said, I would associate drying agent with something like MgSO4 which is used to do what it says on the tin really... mop up the excess water in the vessel. Whereas a dehydrating agent I would say is on a more molecular level to remove water from a molecule.
Original post by ChrisBee
Thanks for the response, does anyone else agree?


Just be a bit careful about the phrase "removing water from a molecule".

It can mean just that, i.e. removing water molecules from other compounds (e.g. dehydration of hydrated copper(II) sulphate), but usually means "removing the elements of water from a molecule". It is usually one hydrogen from one atom and an OH group from another nearby location.
(edited 10 years ago)
Drying agents bring about a physical change with no change in the composition of the compound whereas a dehydrating agent brings about a chemical change and a change in the composition of the compound.
Drying agents bring about a physical change with no change in the composition of the compound whereas a dehydrating agent brings about a chemical change and a change in the composition of the compound.
You can say that again!
Original post by charco
You can say that again!


Oh you.
Original post by charco
You can say that again!



Original post by Infraspecies
Oh you.


Oh the trolling
Original post by JMaydom
Oh the trolling


D:
when asked the function of a drying agent or a dehydrating agent , could you say that it removes water?

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