What are Lewis structures used for in chemistry?

Lewis structures serve a crucial role in understanding the electronic arrangement of molecules by visually representing valence electrons and how they bond with one another. In these structures, dots are used to signify valence electrons, while lines depict covalent bonds formed between atoms. This visual representation helps chemists predict the arrangement of atoms in a molecule, the types of bonds that may exist (single, double, or triple), and the overall connectivity of different atoms within the molecule, which is vital for predicting reactivity and properties.

Lewis structures are not designed to illustrate ionic bonds specifically, nor do they provide information about the three-dimensional shape of molecules, as they are primarily two-dimensional representations. Furthermore, they do not involve calculations of molecular weights; instead, they focus on electron arrangements and bonding. Thus, the primary purpose of Lewis structures is to clarify the roles of valence electrons and bonding in molecules.