Demonstrate electrochemistry with a gravity cell

Discover how to demonstrate a gravity cell and use it in your post-16 lessons on electrochemical cells and redox reactions. While school electrochemistry focuses on potential difference and its relationship to thermodynamics, when you build a cell, you want it to do something. The classic cell setup with metal strips and beakers of salt solutions connected by a salt bridge creates a voltage you can measure, but the high internal resistance means a single cell won’t power much more than a potato clock. The gravity cell configuration keeps everything in one beaker and will power a small motor or buzzer, giving a playful audiovisual demonstration of how a voltaic cell works. Watch the video and download the technician notes for a kit list, tips and safety information.