The term electron cloud is used to describe the area around an atomic nucleus where an electron will probably be. It is also described as the "fuzzy" orbit of an atomic electron.

An electron bound to the nucleus of an atom is often thought of as orbiting the nucleus in much the same manner that a planet orbits a sun, but this is not a valid visualization. An electron is not bound by gravity, but by the Coulomb force, whose direction depends on the sign of the particles' charge. (Remember, opposites attract, so the negative electron is attracted to the positive proton in the nucleus.) Although both the Coulomb force and the gravitational force depend inversely on the square of the distance between the objects of interest, and both are central forces, there are important differences. In the classical picture, an accelerating charged particle, like the...