Final answer:
The VSEPR theory does not assert that electron pairs around the central atom are always arranged tetrahedrally; this arrangement happens only when there are four regions of electron density. The VSEPR model primarily focuses on minimizing repulsion between electron pairs which dictates the geometry of the molecule.
Step-by-step explanation:
According to VSEPR theory, the statement that could NOT be true for ANY molecule is that the electron pairs around the central atom are arranged tetrahedrally as an absolute. The Valence Shell Electron Pair Repulsion (VSEPR) theory explains that the arrangement of electron pairs (including bonding pairs and lone pairs) around a central atom is determined by the principle of minimizing repulsion between these electron pairs. This leads to electron pairs positioning themselves as far apart as possible in three-dimensional space to lower the energy of the molecule. However, while many molecular structures result in a tetrahedral arrangement of electron pairs when there are four regions of electron density around the central atom, other molecular geometries exist such as linear, trigonal planar, bent, trigonal bipyramidal, octahedral, and more, depending on the number and types of electron density regions.
The statement that the valence electron pairs are arranged to minimize repulsion is a core aspect of the VSEPR theory and is true. It's the foundational concept that dictates the three-dimensional structure of the molecule. Other interactions like nuclear-nuclear repulsions and nuclear-electron attractions also influence the molecular structure, but the VSEPR model primarily considers the repulsion between electron pairs.