"Ions"

Readers may already know what an atom is: a number of positively charged protons & uncharged neutrons forming a nucleus, and surrounded by shells or clouds of electrons ... with the same number of electrons as there are protons, for an electrically neutral configuration. Additional info about this is in our FAQ about Faraday's Law Readers have seen metal items made of aluminum, copper, iron, etc. -- i.e., made of large collections of such atoms. If we manage to remove electrons from a metal, however, it is no longer a metal, it becomes something else, a collection of positively charged "ions" rather than atoms. As a general rule when talking about electroplating, galvanic corrosion, and the subjects addressed by finishing.com, ions are more like salt than like metal, and they are soluble (dissolve) in water. The simplest way of envisioning electroplating is that if you immerse two chunks of metal into a conductive solution like salty water, and you connect those two chunks to the opposite ends of a battery, the battery will take electrons from the chunk attached to the positive end of the battery and transfer them to the chunk attached to the negative end of the battery. As electrons are taken from the chunk attached to the positive side of the battery, the atoms on its surface have been stripped of some of their electrons so the metal is converted to positively charged ions which will dissolve into the solution and are attracted to the negative charge of the other chunk of metal. When those ions migrate through the solution and reach the excess electrons on the other chunk they are converted back to metal atoms.