Atomic Structure

Atomic Model

An atom has a small, positively-charged nucleus surrounded by orbiting negatively-charged electrons.

An atom has a small, positively-charged nucleus surrounded by orbiting negatively-charged electrons.

Structure of an Atom

Atoms are very small and have a radius of about 1 × 10 ^ -10 metres. The electrons are arranged at different distances from the nucleus (different energy levels). The radius of a nucleus is less than 1/10 000 of the radius of an atom. Most of the mass of an atom is concentrated in the nucleus.