Atomic Structure and Bonding

Atomic Structure and Bonding

1. the structure of an atom

   • an atoms nucleus contrains protons and neutrons
   • electrons orbit the neucleus in shells
   • same number of electrons and protons
   • electron arrangement
     • maximum of 2 in first shell
     • maximum of 8 in subsequent shells
     • electron configuration = [2,4]
     • elements with a full outer shell are unreactive
     • periodic table
       • horizontal rows = periods
       • vertical rows - groups

2. ionic bonding

   • non-metal + metal
   • involves giving and receiving electrons
     • E.G. sodium [2,8,1] looses 1
   • when looses an electron there is 1 more proton than electron
     • this means the atom has a plus charge
   • in chemical bonding ions are formed
   • quick way of working out the charge of an ion
     • number of charges on an ion formed by a metal is equal to the group number of the metal
     • number of charges an ion formed by an non-metal is equal to the group number minus 8
   • can be drawn using a dot and cross diagram

3. covalent bonding

   • non-metal and non-metal
   • atoms share electrons to complete shells
   • all atoms attain noble gas structure - complete outer shells
   • all new particles formed are netural

Images and files in the map