1) A lemon battery can generate a small electric current without chemicals by using a lemon as an electrolyte between two different metal electrodes, such as copper and steel clips. 2) The acidity of the lemon plays the role of the electrolyte, allowing the transmission of electric current when the electrodes are connected by a circuit such as the tongue. 3) All batteries work on the same principle of converting chemical energy into electrical energy through reactions between different metal electrodes separated by an electrolyte, which was discovered by Alessandro Volta with his first battery in 1780.

1. NATURAL SCIENCE EXPERIMENT Nº2 (UNIT 9)
‘LEMON BATTERY’
Did you know that the lemon is not only used to squeeze the juice but also to
make a battery without using chemical materials? With this physics experiment,
you can make lemons, a battery that really works and provides current.
What do you need?
• Lemons
• A piece of copper wire
• Clips
What is there to do?
1. Unfold steel clips to stretch them to the fullest.
2. Take a piece of copper wire and cut the two pieces of metal to have the same length.
3. Nail the copper wire and the clip side by side in the lemon.

2. 4. Touch the extremities of the two pieces of metal with your tongue. You'll see how itchy it is, like a
cramp! Don't worry, it will be very soft.
How does it happen?
The itching you feel on the tongue is a tiny (and harmless) electric shock. It is because with the lemon
we create a natural battery. The threads of different materials, the acid of the lemon and the
moisture of the tongue form an electrical circuit, a kind of mini battery. The acidity of the lemon plays
the role of electrolyte. This is what liquids that are capable of transmitting the electric current.
Why does it happen?
The Italian physicist Alessandro Volta created the first battery in 1880. With silver and zinc washers
separated by cardboard impregnated with brine. He realized that several metals in contact with a wet
element gave off some current. It was the beginning of the stack. Although this discovery of Volta had
to be improved by other scientists to get to get a really powerful battery.
There are currently different types of batteries: cylindrical batteries that are used only once, car
batteries that are charged directly with the operation of the alternator, nickel-cadmium batteries
that can be recharged many times. All batteries work the same way: they convert chemical energy into
electrical energy. A battery consists of one or several batteries. Each of them is composed of two
electrodes and a chemical (electrolyte) that carry tiny particles (electrons). The electrodes are always
composed of different materials so that there is always one that has more electrons than the other.
The surplus of electrons circulates through an electrical circuit that is attached to the battery. In
addition, physicist Alessandro Volta was the one who named the electric unit by calling it Volt.