What is the electronic geometry and bond angle for CH4?

In the case of methane (CH4), the molecule exhibits a tetrahedral electronic geometry. This is determined by the presence of four bonding pairs of electrons surrounding the central carbon atom. Each hydrogen atom forms a single covalent bond with the carbon, utilizing all four valence electrons of carbon.

The arrangement of these four bonding pairs leads to a three-dimensional configuration that minimizes the repulsion between these electron pairs, consistent with VSEPR (Valence Shell Electron Pair Repulsion) theory. The ideal bond angle for a tetrahedral geometry is approximately 109.5 degrees. This angle arises because the electron pairs orient themselves in such a way to be as far apart from each other as possible, achieving maximum spatial separation.

Other options describe different molecular geometries which do not apply to methane:

• A linear structure would indicate the presence of two bonding pairs and hence a bond angle of 180°, which does not represent CH4.
• A trigonal planar arrangement, which typically involves three bonding pairs and a bond angle of 120°, is also not relevant because methane has four bonding pairs.
• A trigonal bipyramidal geometry involves five bonding pairs with distinct bond angles of 90° and 120°, again not applicable to CH4.

Therefore