The atom consists of a tightly packed nucleus made up of protons and neutrons, with varying numbers of electrons circling around it, much as the planets of our solar system orbit the sun. This movement of electrons actually results in a minute magnetic force within the atom. Most electrons are paired in such a way that their magnetic fields cancel each other. When all the electrons in an atom are paired, the net magnetic field is zero. Metals composed of such kind of atoms are nonmagnetic.
But if the atom has unpaired electrons, it has a net magnetic moment, as the scientists call it. The strength of this magnetic moment determines how the atoms line up in the solid metal. In most metals, the agitation of the atoms at ordinary temperatures is great enough to overcome the magnetic forces, and the atomic magnets are disarranged, in random directions. The net resultant of the magnetic fields of a large number of atoms averages out to zero.
But if the atom has unpaired electrons, it has a net magnetic moment, as the scientists call it. The strength of this magnetic moment determines how the atoms line up in the solid metal. In most metals, the agitation of the atoms at ordinary temperatures is great enough to overcome the magnetic forces, and the atomic magnets are disarranged, in random directions. The net resultant of the magnetic fields of a large number of atoms averages out to zero.