coins out of the liquid. rinse them really well under running water, and put them on a paper towel to dry. write "rinsed" on the second paper towel.
6. put a nail and a bolt into the liquid. lean another nail against the side of the bowl so that only part of it is in the liquid.
7. after 10 minutes, take a look at the nails. are they a different color than they were before? is the leaning nail 2 different colors? if not, leave the nails in the bowl and check on them again in an hour or so.
8. what's happening to the bolt? you may see lots and lots 