Although the L shell has a capacity of 18 electrons, why does having eight electrons make the atom stable ? Why do atoms need to have ONLY EIGHT electrons on their valence shell in order to be stable?
Although the L shell has a capacity of 18 electrons, why does having eight electrons make the atom stable ? Why do atoms need to have ONLY EIGHT electrons on their valence shell in order to be stable?
Hi Mayuka,
The capacity of L shell is 8 and not 18. The capacity of M shell is 18.
The outermost sub-shell of an atom (which is s and p put together) cannot accommodate more than 8 electrons, even if shell has a capacity to accommodate more electrons. This is a very important rule and is also called the Octet rule. The presence of 8 electrons in the outermost shell makes the atom very stable as its capacity is 8 (full). Bohr, using quantum mechanics, said that maximum number of electrons that can be accommodated in a shell is given by 2n^2 where n = shell number and along with Bury gave some rules in the accommodation of electrons in the outer most shell to be 8, so called octet rule.
Hi Mayuka,
The capacity of L shell is 8 and not 18. The capacity of M shell is 18.
The outermost sub-shell of an atom (which is s and p put together) cannot accommodate more than 8 electrons, even if shell has a capacity to accommodate more electrons. This is a very important rule and is also called the Octet rule. The presence of 8 electrons in the outermost shell makes the atom very stable as its capacity is 8 (full). Bohr, using quantum mechanics, said that maximum number of electrons that can be accommodated in a shell is given by 2n^2 where n = shell number and along with Bury gave some rules in the accommodation of electrons in the outer most shell to be 8, so called octet rule.
