The illustration depicts the formation of an ionic chemical bond between sodium and chlorine atoms. Why is the resulting compound more stable than the individual atoms?

Generally put, all atoms that lack the 8 valence electrons or maximum amount of electrons in its outer shell "want" to be chemically stable. To become stable, atoms that lack a filled outer electron shell, like Sodium, Na, have to give away its two outermost electrons to chlorine, Cl, which only needs one more electron to completely fill its outermost electron shell. Thus, through this process, the newly formed compound, Sodium Chloride, otherwise known as table salt, is chemically balanced as well as stable.