Answer:
The answer to your question is below
Step-by-step explanation:
Valence electrons are the electrons located in the outermost shell of an atom.
In the periodic table atoms are ordered in groups which considered the valence electrons.
For example:
Group IA: all the atoms in this group have 1 valence electron.
Group IIA: the elements in this group have 2 valence electrons.
Group IIIA: the elements in this group have 3 valence electrons.
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Group VIIA: the elements in this group have 7 valence electrons.
Group VIIIA: the elements in this group have 8 valence electrons.