Towards the end of my school year, I stopped by my old chemistry teacher’s office with five bottles full of Pepto-bismol and a puzzling question: can I turn this medicine, which I took last night, into pure bismuth? Sure enough, in science teacher fashion, she responded, “We won’t know until we try it out!” I had found this lab searching for ways to recycle old medicine on the internet a couple of days before. I knew that medicine often expired a while after its expiration date, but when it did expire, I didn’t want it to go to waste. This lab (if it works…) will be able to turn expired, commonly used Pepto-bismol into Bismuth, which in addition to being used for pharmaceuticals, can also be used for solders and other alloys and pigments for cosmetics, atomic fire alarms and sprinkler systems, ceramics, and glass! After finding the steps, I went to CVS with my footlong coupon, bought five bottles of Pepto-bismol, and found my old chemistry teacher the next day. Here are the steps that the slide show photos follow:
- Grind up the Pepto-bismol with a mortar and pestle to create better surface area
- Add 6 parts water with every one part hydrochloric acid to the beaker. The acid reacts with the bismuth subsalicylate to create bismuth chloride
Reaction: C7H5BiO4 + 3HCL(aq) -> C7H6O3 + BiCL3 + H2O
- Let the beaker sit for an hour to allow the bubbles to subside
- Filter the solid from the liquid using a filter of any kind and a funnel
- Add aluminum foil to the liquid and watch it react!
Reaction: BiCL3 + H2O + Al -> Bi(s)
- Let it dry and give yourself a pat on the back because you are saving the world
Intro video:
https://drive.google.com/file/d/1viXFjnbajnrGv9jK3viFr9Wf_mAgeR4F/view?usp=drive_link