The periodic table

The periodic table

1. Divided into metals and non metals

2. 75% of the elements are metals

   • In the 2 left hand columns - groups 1 and 2
   • In the central block - the transition elements

3. 25% of the elements are non metals

   • Found in the groups at the right hand side of the table

4. The symbols in the table represent atoms

   • O represents an atom of oxygen
   • Na represents an atom of sodium

5. Elements in the table are arranged into vertical columns, called groups

   • Each group contains elements with similar properties

6. Atom structure

   • Zinc = p = 30 n = 35 e = 30
     • Oxygen = p = 8 n = 8 e = 8
       • Potassium = p = 19 n = 20 e = 19
         • Lead = p = 82 n = 125 e = 82
   • Neutrons = atomic mass - protons
     • Zinc = atomic mass 65 - atomic number (protons) 30
       • Oxygen = atomic mass 16 - atomic number 8
         • Potassium = atomic mass 39 - atomic number 19
           • Lead = atomic mass 207 - atomic number 82

7. Electronic structure of atoms

   • Hydrogen: atomic number 1 electronic configuration 1
     • Helium: atomic number 2 electronic configuration 2
       • Lithium: atomic number 3 electronic configuration 2,1