A primary electric cell in which the electrolyte is a liquid is called wet cell.
- Copper Coin
- Zinc Washer
- Piece of Cardboard
What’s going on?
Batteries are devices that convert chemical energy into electrical energy. When two different metals are connected by an electrolyte, a chemical reaction occurs at each metal surface, called electrodes, that either produces or uses electrons. When these electrodes are connected by a wire, electrons will move from one surface to the other, creating an electric current.
By sanding off one face of a penny, you create a zinc electrode that can pair with the copper electrode on the face of the next penny. The mat board soaked in salty vinegar water serves as the electrolyte between the two terminals. Each zinc-mat board-copper stack represents one individual cell. By stacking additional mat boards, pennies and zinc, you’ve created a battery, which is a series of electrochemical cells. This is also called a Voltaic pile, which is named after Alessandro Volta, who created the first battery in 1800 by alternating zinc and copper electrodes with sulfuric acid between them. In Volta’s battery and your penny battery, an oxidation reaction occurs at the zinc electrode that produces electrons and a reduction reaction occurs at the copper electrode that consumes them.