Exceptions to the Octet Rule

Reminder about the Octet Rule

"Atoms tend to gain, loseor shareelectrons until they are surrounded by 8 valence electrons"

Exceptions to the Octet Rule

Example on Atoms with a total odd number of electrons: NO Molecule

Total number of valence electrons = 5 (of N) + 6 (of O) = 11 (odd number)
no-lewis

Example on Less than Octet: BF3 Molecule

bf3-lewis

Despite these correct resonance structures, they are not possible due to the unacceptable formal charge on F.

Example on More than Octet: PCl5 Molecule

pcl5-lewis


For more details, please contact me here.
Date of last modification: Summer , 2019