Final answer:
The valence electron is the outermost electron-occupied shell of an atom and is represented in Lewis structures. The VSEPR model predicts the arrangement of bonded atoms in a molecule based on valence electron pairs.
Step-by-step explanation:
The valence electron is a description of the outermost electron-occupied shell of an atom. In chemistry, the valence electron is represented in Lewis structures as dots around the chemical symbol of an atom. The valence-shell electron-pair repulsion (VSEPR) model is used to predict the arrangement of bonded atoms in a molecule or polyatomic ion based on the valence electron pairs. The VSEPR model assigns an AXmEn designation to the molecule or ion, where A is the central atom, X is a bonded atom, E is a nonbonding valence electron group (usually a lone pair of electrons), and m and n are integers.