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Chemistry
These hands-on activities investigate phenomena that arise from molecules and atoms interacting and transforming in different ways. Build a battery and light up an LED without much more than the change in your pocket.
All content in “Chemistry”

Chemistry Introduction

Chemistry and chemical reactions can be electric or explosive, sweet or sour, powerful or perplexing.

Penny Battery

Can you light up a room with just five cents? A battery is a device that converts chemical energy into electrical energy. This activity, developed and demonstrated by Julie Yu, director of the Exploratorium Teacher Institute, shows you how to build a battery strong enough to power an LED for a whole day—using nothing more than a few pennies and a salty solution. Watch the videos to learn how to build a battery of your very own, and light the way for other chemistry lovers.