Because it is simple for the learners to visualize and use, the octet “rule” is “often presented as an obligatory condition for “proper” bonding; this causes some students to have difficulties accepting anything that is not clearly explicable in “octet” terms”.
For students in the 14−16 age range the octet “rule” is a useful one: it provides a suitable set of criteria to work from
that will lead to examination success since the molecules they will be tested on are limited to those involving covalent
bonding of atoms of period 1 and 2 elements. If students are to study chemistry no further than this level, then there may be no problem with them not exploring the limits of the rule.
However, students’ attachment to the octet rule has been widely criticized as leading toward a number of misconceptions
and hindering further development of more advanced ideas on chemical bonding.3 For many students there is a great deal of benefit in introducing them to the idea that “rules” they may have been presented with may be simplifications and, as such, have limitations.