Here, it is essential to understand that a higher number of valence electrons will strengthen the ability of an atom to accept the electrons rather than donating. Moreover, uneven or unpaired electrons compel them to participate in the bond formation.
Because they are present in the outermost shell, the hold of the nucleus is weak on them. The electrons present in the outermost shell of an atom are called valence electrons. Valence electrons in Phosphorus and Fluorine atom On the other hand, a single fluorine atom has seven valence electrons with a d of one to complete its octet and reach a stable condition. One phosphorus atom has five valence electrons, having a scarcity of three to complete its outermost shell or octet. As per this rule, the maximum number of valence electrons an atom can have is eight.
