Bonding Notes

Covalent bonding:

Rules of writing lewis structures for covalent bonded ions and molecules.
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Determining if a bond is ionic, covalent, or polar covalent.


  • The type of bond is determined by the electronegativities of the elements involved.
  • The electronegativity difference (the change in electronegativity) between the two atms will determine if it is ionic, covalent, or polar covalent.
  • Ionic Bonds have very different electronegativities because one bond is giving up it’s electron and another is gaining an electron
  • Ionic Bonds are formed if the electronegativity difference is > 1.7(Compounds between metals and non metals are usually considered ionic unless the charge to radius ratio is considered and the bond can become polar in exceptional cases)
  • Covalent bonds have very similar electronegativities because they both want to keep their electrons so they share electrons. Their electronegativity difference is <0.4
  • Electronegativity differences of 0.4 -1.7 would form a bond called polar covalent bond.
  • Polar Covalent Bond (Show how a bond looks and how it is polar or not)
  • (Show delta + and delta -)