Final answer:
Metals tend to lose electrons to become cations, while nonmetals tend to gain electrons to become anions. This trend can be explained by the number of valence electrons and the desire for stability.
Step-by-step explanation:
Metals tend to lose electrons and nonmetals tend to gain electrons due to their different properties and electron configurations.
Metals have few valence electrons and tend to increase their stability by losing electrons to become cations. Nonmetals, on the other hand, have more valence electrons and increase their stability by gaining electrons to become anions. This trend can be observed using the periodic table.