Final answer:
Ions form when atoms gain or lose electrons to achieve a full valence shell, following the octet rule. Atoms with more valence electrons tend to gain electrons and become anions, while those with fewer valence electrons tend to lose them and become cations.
Step-by-step explanation:
Ions are formed when an atom either loses or gains electrons to achieve a more stable electron configuration.
Atoms with more valence electrons often gain electrons to become anions, which are negatively charged ions.
This happens because elements tend to follow the octet rule, seeking to have eight electrons in their valence shell, similar to the electron configuration of noble gases, which are inherently stable.
When an atom has one to three valence electrons, it may lose these electrons to become a cation, a positively charged ion.
This is because these atoms can achieve a stable octet by revealing a complete valence shell in the lower energy level.
Metals, having few valence electrons and generally low electronegativities, often form cations in this way.
In contrast, nonmetals tend to gain electrons to achieve a full valence shell because they have more valence electrons and higher electronegativities, thus becoming anions.
The complete question is:
Ions with more valence electrons gain electrons to become stable. Justify!