The size of an atom is too small to imagine. Counting the number of atoms in even a microscopic amount of material is an impossible task – it would take a billion years! It turns out, however, that it is possible to apply a thin surface coating of metal atoms onto another metal. This is done to change the properties of the underlying or base metal. In this experiment, the thickness of a zinc metal coating on galvanized iron will be determined and used to “count” the number of layers of atoms in the coating.