Chapter 4 ionic and covalent bonds

• Metals (cation)+ and non-metals (anion)-


  • Tend to form cations by losing valence electrons to attain the noble gas configuration.
  • Tend to form anions by gaining electrons in their valence shell to attain the noble gas configuration
• Formation of ionic compounds

  eg Sodium + Chlorine → Sodium Chloride
• Ionic compounds


  Usually formed when metal reacts with non-metal
• Ionic bond


  Strong electrostatic forces of attraction between the positively charged ion (cation) and negatively charged ion (anion)
• Noble gases


  • Last elements in each row of periodic table
  • Have full valence shells
  • Chemically unreactive
• Covalent Bond


  Forces of attraction between two non-metal elements by sharing electrons in their valence shells
• Valency


  Number of electrons that must be lost, gained or shared in order for an atom to attain a noble gas electronic configuration
• No. of electrons shared = No. of electrons the atom needs to have a full shell
• No. of electrons shared by the atoms must be the same for both elements in the compound to have full valence shells