Science Buddies: "Ask an Expert"

I am currently doing a project that goes with the experiment of whether or not big pieces or small pieces have an effect on the speed of the chemical. Besides Alka-Seltzer tablets, I would like to know if there are chemicals that would give me results of the experiment whether it being fast or slow. I would also like to know if there are big pieces that would dissolve faster than small pieces.

Anything that will dissolve in water: Salt, sugar for example.

Mentos and diet soda sounds interesting.

Other chemistry ideas: http://chemistry.about.com/od/chemistry ... ojects.htm

I don't know of any big pieces that dissolve faster.

Good luck.