In this deck, we'll explore how we can generate electricity using chemical reactions. We'll start with simple chemical cells, which are the basis for batteries, and then move on to a modern technology: hydrogen fuel cells. You'll learn how they work, what they're made of, and the pros and cons of using them as an energy source.

A simple chemical cell can be made by placing two different metals into a solution called an electrolyte. An electrolyte is a liquid that contains ions and can conduct electricity, like a salt solution or a dilute acid. The two different metals create a potential difference, or voltage, which causes electrons to flow from the more reactive metal to the less reactive one. This flow of electrons is an electric current.

The voltage produced by a chemical cell depends on the two metals used. Specifically, it depends on the difference in their reactivity. The greater the difference in reactivity between the two metals, the larger the voltage produced. For example, a cell made from magnesium and copper would produce a higher voltage than one made from zinc and copper, because magnesium is much further away from copper in the reactivity series than zinc is.