An Allegory is used to tell a story that has characters, a setting, as well as other types of symbols, that have both literal and figurative meanings.
Chlorine is counted among this group along with hydrogen (H 2), iodine (I 2), bromine (Br 2), oxygen (O 2), nitrogen (N 2) and fluorine (Fl 2). With seven electrons in its outermost orbit--one electron short of a stable eight-- the element chlorine exists in nature as a diatomic molecule. This arrangement allows two chlorine atoms to share their outermost orbit electrons, achieving stability, compared to the single atom.
An atom such as chlorine (Cl), that contains seven electrons in its valence shell, needs one more electron to have a full valence shell. If we use the same logic as we did for sodium, we should conclude that chlorine would rather gain one more electron than lose all seven of its valence electrons to achieve stability.