Final answer:
Atom characteristics, such as the valence electron pairs, determine the VSEPR shape of a molecule, with electron pairs repelling each other to maximize distance, shaping the molecule's geometry.
Step-by-step explanation:
The characteristics of an atom that determine the VSEPR shape of a molecule are primarily associated with the electron pairs found in the atom's valence shell. The VSEPR theory, which stands for valence-shell electron pair repulsion, suggests that the electron pairs will repel each other and the shape of the molecule will adjust accordingly. This adjustment aims to keep the valence electron pairs as far apart as possible, leading to the molecule's specific three-dimensional geometry. The model differentiates between electron group geometry, which describes the spatial arrangement of both bonding electrons and nonbonding electron pairs, and molecular geometry, which represents the arrangement of the atoms themselves.
Molecules can be systematically classified based on the number of bonding pairs and lone pairs around the central atom. The type of bond, whether single, double, or triple, does not affect the repulsion in the VSEPR model. It is important to note, however, that VSEPR theory simplifies the interactions and does not take into account complexities such as orbital interactions that also influence molecular shape.