What do Lewis dot structures represent?

Lewis dot structures are a visual representation of the valence electrons in an atom. In these structures, the valence electrons are depicted as dots surrounding the chemical symbol of the atom. This method simplifies the understanding of how atoms bond with one another and form compounds, as it illustrates the electrons that are involved in chemical bonding.

By focusing on valence electrons, which are located in the outermost shell of an atom, Lewis dot structures help to depict both the lone pairs of electrons and the electrons involved in bonding. This is crucial because the behavior of electrons in the outer shell is responsible for the atom's reactivity and its ability to form connections with other atoms. Thus, choice C accurately describes the function of Lewis dot structures by highlighting that they represent valence electrons as dots.

In contrast, other choices do not align with the purpose of Lewis dot structures: protons and neutrons (choices A and B) pertain to the atomic nucleus and do not play a direct role in the formation of these structures. The last choice, which refers to bonding pairs of electrons as lines, describes another form of representation called structural formulas, which show bonds specifically as lines rather than individual electron pairs or lone electrons.