Answer
In most elements the outermost ( farthest from the nucleus) electron shell is the valence shell. This is not true of transitional elements ( Groups 3-12 in the Periodic Table) . Valence electrons determine the chemical properties, reactivity and bonding ( type and affinity) of an element. Valence electrons also influence the electrical conductivity of elements
Work Step by Step
Valence electrons are the electrons in the outermost shell of the atoms of an element ( except the transitional elements). Transitional elements, however, may have valence electrons in inner atomic shells.
According to the octect rule, an element is most stable when it has eight electrons in its outermost shell. This is the condition in noble gases which are easily take part in chemical reactions. Chemical elements with one electron or seven electrons in their outermost valence shells are the most chemically reactive, through the donation of an electron in the former case and by acceptance of one in the latter case.
Valence electrons determine chemical properties, reactivity, bonding and electrical conductivity of elements.
