The electron pair geometry for sulfur (S) in sulfur dichloride (SCl2) is bent or angular.
To understand why, we first need to look at the molecular structure of SCl2. In SCl2, sulfur is the central atom, bonded to two chlorine atoms. Sulfur has six valence electrons, and each chlorine atom contributes one electron to form a single bond with sulfur, using up two of sulfur’s valence electrons.
After forming these two bonds, sulfur is left with two lone pairs of electrons. The presence of these lone pairs affects the geometry around the sulfur atom. According to the VSEPR (Valence Shell Electron Pair Repulsion) theory, the lone pairs will repel the bonded pairs, resulting in a bent shape for the molecule.
When we consider the arrangement of the two bonded pairs and two lone pairs, the idealized arrangement that minimizes repulsion is tetrahedral. However, because we can only see the bond pairs, the actual shape of the molecule appears bent. The bond angle is approximately 104.5 degrees, which is slightly less than the typical 109.5 degrees in a tetrahedral geometry due to the repulsion exerted by the lone pairs.
In summary, the electron pair geometry around the sulfur atom in SCl2 is based on a tetrahedral arrangement of electron pairs (including lone pairs), but the molecular geometry, considering only the atoms, is bent.