Question - Explain how the need for an atom’s outer shell to be filled with electrons contributes to bonding.

Explain how the need for an atom’s outer shell to be filled with electrons contributes to bonding.

ANSWER:

The element’s atomic number will determine the extent to which its outer layers are popu‐ lated with electrons. If the outer shell is not quite full, the atom may gain electrons to fill them and become an anion (negative charge). If the outer shell has only a few electrons, it may lose them and become a cation (positive charge). Cations and anions attract each other to form mol‐ ecules with ionic bonding.