Hi Everyone

So.. I had this idea on how to perform an effect, but need some help from you guys.
I am looking for a substance (liquid) which:

a) is not dangerous for health when it gets in contact with your skin
b) produces some effect (best would be smoke) when it contacts either a specific material or maybe another substance (which could be used to coat something like a piece of wood or a table).

Let's say it will be something like a Russian roulette with chemicals. Don't want to give away too much for now... but if someone can think of a substance like this, please let me know. I appreciate your help!


I forgot to mention... the reaction should look a bit like acid burning through things... however the burning is not necessary, smoke or little bubbles (like when acid starts burning through material) are good enough.

Something like how Alka Seltzer reacts when it gets wets? Bubbles and looks like acid burning.

Just a thought.