[bhshawnbob]

I'm interested in the reaction of NH4Cl (sal ammoniac) and water.  I've been trolling google for basic info.  Mostly I end up with chemistry tests.  Specifically I'm interested in the higher temperature reactivity of a supersaturated solution.

#1) I know the reaction is endothermic but I'm looking for the actual KJ of heat absorbed/mol of NH4Cl.

#2) Where can I find solubility info on the saturation of NH4Cl in water?

#3) MOST IMPORTANT: What are the issues of this reaction at higher temperatures. I.E. if this reaction took place inside a sealed vessel up to 65 deg C.  Does it make gasseous HCl or ammonia, and is it reversable if cooled?  I don't want to make any dangerous byproducts.

#4) What happens if the mixture goes up to 175 deg. C?  Would this be really bad?
What is the worst case scenario with this reaction?

[xiankai]

try googling for the MSDS of ammonium chloride or look for it on wikipedia.

i believe it sublimes at higher temperatures.

[bhshawnbob]

Thanks a bunch.

I've seen the MSDS, but I'm not sure if you get HCl(g) out of the reaction or if it's considered dangerous to do this reaction at higher temperatures of 65 deg C.  If the reaction were to happen at up to 175 deg C, would it be dangerous?  I'm trying not to make a bomb or acid gas, and normally I would want this reaction to occur at about 50-75 deg C, but the worst case would be up to 175.

P.S. I'm still not sure how to find the KJ/mol of heat in the reaction per mole NH4Cl reacted.  I also need to know how what the saturation amount per unit water is at room temp.
Perhaps it's all just basic chemistry that I need to brush up on.
Can someone recommend any further reading?

Thanks again,
Shawnbob

[xiankai]

if u heat it beyond 100 celsius, all the water will be boiled off leaving you with anhydrous NH4Cl, which would most likely decompose into toxic HCl and NH3 fumes.

the reaction between ammonium chloride and water is that of dissociation of a salt... so u'll want to find the heat of solvation of ammonium chloride.