My how things have changed, I went to our local chemist shop when I was 10 and told the pharmacists I was doing a school project on "Gunpowder" Not only did he tell me how to make it, he ordered in the ingredients.
1/3 Carbon
1/3 part A won't say.
1/3 Part B still won't say.
But BANG! she went. Great fun!
Later I made a working Bazooka! but you can't prove that.