Electricity flows as an electrical current in a wire. This flow is made up of electrons which are subatomic particles. It is therefore necessary to understand some basic atomic structure.
Below is a representation of the Bohr model of an atom.
| Symbol | Particle | Atomic Mass | Atomic Charge |
|---|---|---|---|
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An atom is made up of a nucleus which contains protons and neutrons. Electrons orbit this nucleus in so called shells. The shells or orbits do not actually exist, they represent different energy levels for the electrons.
An atom always has zero charge. This means that it must have the same number of protons as electrons. If an atom looses or gains one or more electrons is forms an ion.
Test yourself with the following Java Applet:
