ETS Major Field Test Chemistry Practice Test 2026 – Complete Preparation Guide

The molecular geometry of CH4, or methane, is tetrahedral. This arrangement arises from the need to minimize the repulsion between the four bonding pairs of electrons that surround the central carbon atom. According to VSEPR (Valence Shell Electron Pair Repulsion) theory, the electron pairs will spread out as far as possible, leading to equal angles of 109.5 degrees between them.

In methane, the central carbon atom is bonded to four hydrogen atoms through single covalent bonds. As a result, the four hydrogen atoms occupy the corners of a tetrahedron with the carbon atom at the center. This spatial arrangement allows for the most stable configuration, minimizing electron pair repulsion, which is the hallmark of a tetrahedral geometry.

This is why the answer is tetrahedral, as it accurately describes the three-dimensional structure that results from the bond angles and the positions of the hydrogen atoms relative to the carbon atom.