9. The octet rule is
a rule which states that elements like to have their valence shells completely
full, which gives them the same composition as a noble gas.
a. In order for an
element to achieve an octet and mimic the composition of a noble gas, the
valence shell must be full.
B Elements with only
one shell, the rule of the first shell of electrons or s orbitals, defies the
octet rule. Within this rule, helium,
hydrogen and Lithium; helium is content with its two electrons filling the
first shell, hydrogen needs to gain one to fill its shell, and lithium also
needs to gain one to fill its shell.
c. Elements in the
3,4,5,6, and 7 periods can expand their octet because their electrons can
absorb more energy and move to a higher energy level.
