I`ve never had any joy with the stuff myself, It`s not so much the clumping as it never seems to get dry enough to do that it`s always just a little damp, and on bad RH days it can even wet surfaces if left out.
yes NaOH will indeed get quite toasty when you add it to water, in fact if you add too much at once to too small a quantity of water it will even Boil!
the AN will more than counter that though
in fact an interesting trick is to get some in the bottom of a vessel, boil a kettle, pour the water in, wait a few seconds to say Abracadabra, and then put your hand in it, the heat is lost almost instantly and leaves you with a soln just under room temp.
looks really scary, but quite harmless.
and BTW, DON`T do this unless you know EXACTLY what you`re doing! and NEVER EVER show this to a child!
Edited by YT2095, 14 August 2007 - 05:15 PM.