Atoms

Atoms

1. All susbstances are made up of atoms

   • Atoms have a radius of about 0.1 nanometres
   • Atoms are neutral- have no charge.
     • This is because they have same number of electrons and protons.

2. Proton

   • Mass: 1
   • Charge: +1

3. Neutron

   • Mass: 1
   • Charge: 0

4. Electron

   • Mass: very small
   • Charge: -1

5. Atomic number and mass number

   • Atomic number tells you how many protons there are.
   • Mass number tells you the total number of protons and neutrons in the atom.
   • Number of neutrons = atomic number - mass number