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
Acorn Atom Acorn Atom The Acorn Atom is a home computer made by Acorn Computers Ltd from 1980 to 1982, when it was replaced by the BBC Micro. The Micro began life as an upgrade to the Atom, originally known as the Proton. The Atom was a progression of the MOS Technology 6502-based machines that the company had been making from 1979. The Atom was a cut-down Acorn System 3 without a disk drive but with an integral keyboard and cassette tape interface, sold in either kit or complete form. In 1980 it was priced between £120 in kit form, £170 ready