The 5-6th graders did a lab today trying to determine if starch (aka amylose) is present in various foods. I had them bring a fruit/vegetable from home and we dripped iodine on the items to see if they turned a blackish purplish gray color. It was pretty neat! And it didn't take super long.
I'd given a big speech before we started about how we needed to be careful with the iodine because it can stain your hands and it can be toxic if you get it in your mouth... I was probably a bit over dramatic. We used pipettes to drip iodine on the items and one of the pipettes sputtered iodine all over one of the 6th grade girls! She was not happy. Her mouth was closed and we were wearing aprons and goggles, but still, the iodine splattered all over a sleeve of her sweatshirt.
In an interesting development, the iodine that landed on her lab sheet turned black, indicating starch present in the paper. (Coffee filters we found didn't have any starch). The drops on her sweatshirt stayed brown, so we concluded there isn't any starch in her sweatshirt. At least we got something out of the little spill!
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