12 replies to this topic

[fruitfulsteve]

is nh4clo4 famously hydroscopic or is my garage very damp(it don't seem damp) ?

[fruitfulsteve]

is nh4clo4 famously hydroscopic or is my garage very damp(it don't seem damp) ?

is nobody answearing because i shouldn't be messing with the stuff if i don't know about it allready ?

[pyrotrev]

It's slightly that way inclined I believe, but not seriously. But if you mix it with any nitrates or magnesium, you will form something that will turn into a very damp mess. BTW it's spelt HYGROSCOPIC guys.

Edited by pyrotrev, 18 February 2009 - 01:21 PM.

[fruitfulsteve]

It's slightly that way inclined I believe, but not seriously. But if you mix it with any nitrates or magnesium, you will form something that will turn into a very damp mess. BTW it's spelt HYGROSCOPIC guys.

thanks, sorry about the rubbish spelling( no spell checking thing on this this contraption ).time to try out my cunning invention!!!
thanks again ffs

[Creepin_pyro]

Ammonium Perchlorate is more hygroscopic than Potassium Perchlorate but not massively so. Apparently it has a tendency to want to hold on to any water it absorbs but I've never attempted drying any personally.

With regard to your second post, you should really read up about this chemical. Compositions made with it can be very shock sensetive, you must never ever contaminate it with Chlorate, and as Trev mentioned there are other considerations too. Cover all theoretical issues before any practical experimentation.

[fruitfulsteve]

Ammonium Perchlorate is more hygroscopic than Potassium Perchlorate but not massively so. Apparently it has a tendency to want to hold on to any water it absorbs but I've never attempted drying any personally.

With regard to your second post, you should really read up about this chemical. Compositions made with it can be very shock sensetive, you must never ever contaminate it with Chlorate, and as Trev mentioned there are other considerations too. Cover all theoretical issues before any practical experimentation.

thanks, i do read up a bit and certainly take note of any no no's, i think the chlorate mix can produce ammonium chlorate (correct me if i'm wrong) i know thats dodgey. but rest assured any experimentation i do is on a very small scale,and not done in the kitchen,as for reading i'm currently working through ' the dummies guide to chemistry' and 'a professionals guide to pyrotechnics' but i don't absorb information quickly!!!
thanks again ffs

[pyrotrev]

To be precise, pure stuff will absorb 0.19% moisture in 2 days at 80% RH. That seems to be enough to make the powder slightly clingy in my experience, though it doesn't affect the burning as far as I can see. One other incompatibility to watch out for is reaction with transition metals to form the corresponding perchlorates which are meant to be pretty dodgy substances when dry

Edited by pyrotrev, 19 February 2009 - 01:40 PM.

[fruitfulsteve]

To be precise, pure stuff will absorb 0.19% moisture in 2 days at 80% RH. That seems to be enough to make the powder slightly clingy in my experience, though it doesn't affect the burning as far as I can see. One other incompatibility to watch out for is reaction with transition metals to form the corresponding perchlorates which are meant to be pretty dodgy substances when dry

do you mean the actual metal or the compounds?
ffs

[spanner]

do you mean the actual metal or the compounds?
ffs

The salts as well.

[pyrotrev]

Aye, both salts and the more reactive metals as well I guess. I know for sure that copper will react with AP, and I suspect uncoated iron would as well.

Edited by pyrotrev, 20 February 2009 - 01:21 PM.

[Potassium chlorate]

All salts soluble in water are probably somewhat hygroscopic. If they can dissolve in water, they're probably inclined to absorb it from the air. Very simple and not scientific theory, but it seems logical.

[E-tech]

Just considering the 'clumping' problem that the dampness can cause. Has anyone tried mixing something like Cab-O-Sil into the
chemical they are working with? As little as 0.25% by weight can pretty much stop all caking/clumping effects.

[fruitfulsteve]

i have now transfered mine to a new jar and put some silica with indicator in the lid i'll keep you posted!!
ffs