From: Katie Johnson (firstname.lastname@example.org)
Date: Thu Feb 20 2003 - 19:33:19 EST
I also thought the marble activity was great!
I do a reaction similar to the iodine clock reaction, but I use sodium
thiosulfate and hydrochloric acid. The students do a serial dilution with
the thiosulfate solution and time how long it takes to become so opaque
that they can no longer see a standard mark through the solution.
Madison East High School