Atomic structure and the periodic table

The nucleus:

• sits in the middle of an atom
• contains protons (+ charge) and neutrons (0 charge) 
• Has a radius of around 1x10-14M
• It has a positive charge, thanks to the protons. CHEERS
• most of the mass is in the atom

The Electrons:

• move around the nucleus in electron shells
• they're negativley charged, and very small, but they take up a lot of space.
• the volume of their orbit determines the size of the atom
• Electrons have virtuaaly no mass.

1) atoms are neutral…