valence shell
Noun
Meaning
valence shell (plural valence shells)
(chemistry) the outermost shell of electrons in an atom; these valence electrons take part in bonding with other atoms
Examples
It is inert to most common chemical reactions, such as combustion, because the outer valence shell contains eight electrons.
It is inert to most common chemical reactions (such as combustion, for example) because the outer valence shell contains eight electrons.
Since the electrons added fill the (n-1)d orbitals, the properties of the d-block elements are quite different from those of s and p block elements in which the filling occurs either in s or in p-orbitals of the valence shell.
The valence shell has eighteen electrons – ten more than the eight found in the valence shells of the noble gases from neon onward.
This is caused by the filling of the valence shell of the atom; a group 17 atom releases more energy than a group 1 atom on gaining an electron because it obtains a filled valence shell and is therefore more stable.