The "octet rule."
Nobel gases are relatively nonreactive because they have eight electrons in the outermost energy level, which is a stable configuration
it has a full octet
there are eight electrons.
The noble gases (group 18/VIIIA/0) are naturally occurring elements that have a full valence shell with eight valence electrons (an octet), except for helium which has two valence electrons (a duet). This makes these elements very stable and very nonreactive.
Helium is the noble gas that does not have eight electrons in its highest occupied energy level. It only has two electrons in its outermost energy level.
The maximum number of electrons in the second energy level of an atom is 8.
Magnesium has two electrons in its first energy level, eight electrons in its second energy level, and two electrons in its third energy level, for a total of 12 electrons.
Carbon has four electrons in the outermost energy level, which is energy level two. It needs eight electrons to have this energy level filled.
In the second energy level, eight electrons are allowed at most.
eight!!
eight
Carbon has four electrons in the outermost energy level, which is energy level two. It needs eight electrons to have this energy level filled.