Atom the nucleus defines to what chemical element the atom belongs: for example, all copper atoms contain 29 protons. The number of neutrons defines the isotope of the element. The number of electrons influences the magnetic properties of an atom. Atoms can attach to one or more other atoms by chemical bonds to form chemical compounds such as molecules. The ability of atoms to associate and dissociate is responsible for most of the physical changes observed in nature and is the subject of the discipline of chemistry. The idea that matter is made up of discrete units is a very old
Captain Atom called on to join him on his quest and provide a way for him to reach Sorcerers' World. Captain Atom appears as one of the central characters in "", a maxi-series that takes place during the wider "Brightest Day" event. At the start of the series, Captain Atom is recruited as part of a massive group of superheroes tasked with hunting down the JLI's founder and Ted Kord's murderer, Maxwell Lord. During an encounter with Max at the Justice League's former New York headquarters, Captain Atom is rendered unconscious alongside Fire, Ice, and Booster Gold. The former Justice League members