Inside the Atom
- Atoms are the building blocks of all matter
- Atoms have a tiny, dense, positively charged nucleus at their centre, with negatively charged electrons orbiting around the nucleus
- The radius of the nucleus is over 10,000 times smaller than the whole atom, but it contains almost all of the mass of the atom
Diagram showing the structure of a Lithium atom. If drawn to scale then the electrons would be around 100 metres away from the nucleus!
Parts of the Atom
- The nucleus contains:
- Protons - positively charged particles with a relative atomic mass of one unit
- Neutrons – no charge, and also with a relative atomic mass of one unit
- Almost all of the atom is empty space, but moving around the nucleus there are:
- Electrons – negative charge with almost no mass (1/2000 the mass of a proton or neutron)