_" Bond Dissociation Energies "_

 Bond Dissociatio  Energies (BDE) :

C = C                                      146 kcal/mol

C – C                                      - 83 kcal/mol

Pi Bond                                   63 kcal/mol

 Explanation : 

          The intention is how to change double bond into single bond by Bond Dissociation Energies.

The energies or BDE of the double bond is 146 kcal/mol and the BDE of the single bond is -83 kcal/mol.

If we give the energy more than 146 kcal/mol ( BDE of the double bond ) into a double bond, so the bonding will be broken.

So from the data, we know that : Pi Bond is the differenc between BDE of double bond and BDE of single bond.

So, Pi Bond must be more than of 63 kcal/mol and must be lest than 83 kcal/mol.

                         83 kcal/mol > π > 63 kcal/mol