Recently I wrote a post for the Jacksonville Moms Blog highlighting some of my favorite science experiments for big kids. These were all done for the Mad Science Party we threw for Cole's 8th birthday. Here are the details for the Disappearing Iodine Water Experiment.
Disappearing Iodine Water
Directions: Fill 2 plastic cups 1/2 way full with ordinary room temperature water. Crush up 2 vitamin C tablets and stir the powder into one of the cups of water. Add approximately a tablespoon of Iodine to the other cup of water. Use your droppers to carefully mix a few drops of iodine water into the vitamin C water. You’ll see that the dark brown Iodine water “disappears” when it hits the vitamin C water. Be careful with this experiment because Iodine will stain clothes (and lab coats). The good news is that some of that vitamin C water will get it out.
Why it works: When Iodine and vitamin C (ascorbic acid) are combined in solution, a chemical reaction takes place. In this chemical reaction, the vitamin C (ascorbic acid) molecule loses electrons, which are transferred to the Iodine molecule.