Two regions
The nucleus, at the centre: tiny, yet it holds nearly all the mass. The electron cloud, around it: it takes up nearly all the volume. An atom is therefore mostly empty space.
6 min
The simplified model of the atom
Nucleus, protons, neutrons, electrons: which carries which charge, why the atom is neutral, and what the atomic number tells you.
The essentials
2
Three particles, three charges
Members only
3
The atom is neutral
Members only
4
The atomic number
Members only