jimmyboy - 22-11-2006 at 18:22
i was wondering what the strongest drying agents would be if you put them in order of strength.. sulfuric acid and calcium chloride come to mind -
would sulfuric steal the water from everything else i wonder? didnt really find any kind of "list of hydrophiles" on google or a measure for them
this is for drying organics - maybe lithium or magnesium metal would be the strongest since they covert water to hydrogen - nah then your left with
hydroxide/alkali that could react - acids are probably the best way to go
i also saw this video on zero point energy - pretty neat -- too bad its a hoax
http://www.youtube.com/watch?v=MLl3VAbUEGY
http://en.wikipedia.org/wiki/Hutchison_effect
[Edited on 23-11-2006 by jimmyboy]
leu - 22-11-2006 at 19:54
It's not nearly as simple as which agent is stronger as this depends on what compound(s) are being dried 
In terms of mode of action, drying agents are either physical or chemical: thus different dessicants are used
depending on the particular circumstances involved 
jimmyboy - 22-11-2006 at 22:04
well suppose i could use any agent in a drying tube -- which would have the strongest drying power...
say you have a choice between - sulfuric - sodium hydroxide - calcium oxide - magnesium sulfate - calcium chloride and silica gel - what would the
order be - strongest to weakest..
[Edited on 23-11-2006 by jimmyboy]
unionised - 23-11-2006 at 12:22
Well, there used to be a table of dessicants in the CRC handbook but I understand that it has been removed from recent editions.
For the record the list is;
P2O5
Mg(ClO4)2
BaO
KOH (Fused)
CaO
H2SO4
CaSO4
Al2O3
KOH (sticks)
NaOH (fused)
CaBr2
CaCl2
NaOH ( sticks)
Ba(ClO4)2
ZnCl2
CaCl2
CuSO4
(CRC's copyright- all errors in copying are my responsibillity)
Their table also gives the mass of water left in a litre of air after drying as a quantitative measure of the drying power.