I am looking for a chemical treatment I can put on a plate, so that when a small amount of water is added, I get an instant whisp of smoke...as if the water were acid. does anyone have any suggestions.

I am not totally sure on this, but dry ice may work..

Please someone tell me if I am wrong or not.. I would like to know too..

-Vinnie

Vinny-
Dry ice wouldn't work, because you can't treat a plate the dry ice. But thanks for the effort. I need something that I can coat or treat a plain dinner plate or saucer with (something ideally not incredible toxic) that will give off some smoke (not billows of smoke or anything, a whisp or puff will be enough) to give the audience the impression that the water is far more sinister then it is (read as acid).

Put a few drops of liquid ammonia on the plate and add some drops of hydrocloric acid (as "water") - or viece versa. You will get smoke.

I thought the whole point of his effect was that it wasn't acid...

Yes, it needs to be water. I want it to be safe. So it needs to be water. Any other thoughts out there?

I can't think of a chemical, but I hit upon another method to get the same effect.
if the plate was sitting on top of an electric hot plate (built into your table?) the water would sizzle and make vapour, much as acid may do if it hits something.

I am guessing you want to pass off water as acid. acid will sizzle and give off gas when it hits metal or some other chemicals, but not an empty ceramic plate, so have a bit of tinfoil or something flat on the plate maybe?

oh, for greater heat transfer the plate should be flush with the hotplate, most plates have a rim underneath.

just brainstorming here, I know its not ideal, hope it helps

Oh, as I was submitting my previous post I had another idea. got to thinking of having 2 dry chemicals that would dissolve and mix when the water hit them.

a strong base will react with tinfoil like a strong acid.. give off heat, release gas (Hydrogen- explosive! but shouldnt be a problem if uncontained) and turn the foil black. so, what you can do is put lye powder on or under the foil. it wont react dry (though with time in a humid environment will absorb moisture from the air) but when you drop the water on it'll dissolve and react. won't be instant though, but not too slow.

otherwise acid + carbonate gives off co2... so maybe (haven't tried this) a dry mix of citric acid crystals and bicarbonate of soda? oh wait.. that sounds a lot like ENO or citro-soda (do you have ENO in the u.s.a? antacid/indigestion? is it called alka seltzer?)

Hmmm interesting ideas. Yes alka seltzer would give a fizzing bubbling reaction. But I am looking for a small single whisp of somke. Thanks for your help.

A tiny film of Potassium metal might work for you (or it might react too violently), but before you even attempt to mess around with that stuff, make sure your read the MSDS on it. (I almost even hate to mention it)
http://www.unitednuclear.com/chem.htm

Yeah I thought about potassium, but it is WAY to sensitive. (potassium literal burns—as on fire—when it comes in contact with water. If I could figure out some sort of potassium dust. That might work. But still nonetheless...I am looking for something a little more, well, safe.

Spackle, get yourself a copy of Lippy's Modern Chemical Magic.
It's a little dated ("modern".. pfft !) but still has loads of valuable information.
Iodine cystals, aluminum powder, ammonium chloride, ammonium nitrate, and zinc dust are all substances which, in proper ratios and combinations, react with water to create smoke and or fire. But don't use all of them together !!!