Water-‘absorbing’ agents and drying substances

[frosch45]

Any help on this problem would be much appreciated, I really think that chemistry is pretty much the coolest thing in the world.

 

Anyway, for extra-credit, my teacher gives a few of us students some interesting chemical problems every now and then.

 

I am wondering if anyone would be able to help with this one.

 

I need to know of a technique or substance--possibly hydroscopic?--that will react with water but not a halogen in order to form a solid precipitate and/or gas so that much H2O (in the problem, bromide was given as the halogen dissolved) could be then removed from the solution--and yes, it could be anything from arsenic to zirconium (obviously, neither would apply, just saying it doesn't necessarily have to be extremely common or easy)

 

I have been looking around a bit--could someone just generally explain the principle of drying agents?

 

I was thinking maybe activated carbon--the solution could be boiled and then run through activated carbon (or similar substance, any ideas?) and returned to another container?? Maybe sodium hydroxide (except that would mess with the bromine, right?)

 

I'm not sure if sparging would work in this situation because of the evaporation removal of the bromide molecules (or ions if aqueous)

 

but it can not be simple distillation:rolleyes: something that would only minimally lose the Br

 

thanks

 

hs

[ecoli]

http://en.wikipedia.org/wiki/List_of_desiccants

[YT2095]

P4O10 should work.