The molecular geometry of the SF2 molecule is Select one: trigonal planar B. linear C. tetrahedral D. octahedral E: bent
The Correct Answer and Explanation is:
The molecular geometry of SF₂ (sulfur difluoride) is bent.
Explanation
Sulfur difluoride (SF₂) is a chemical compound consisting of one sulfur atom and two fluorine atoms. To determine its molecular geometry, we start by looking at the Lewis structure of SF₂. Sulfur has six valence electrons, and each fluorine has seven. In SF₂, the sulfur atom forms single bonds with two fluorine atoms, using two of its electrons to bond. This leaves four electrons (or two lone pairs) on the sulfur atom.
With two bonded atoms and two lone pairs on the central sulfur atom, we use the VSEPR (Valence Shell Electron Pair Repulsion) theory to determine the molecular shape. According to VSEPR, electron pairs around a central atom arrange themselves to minimize repulsion. In SF₂, there are four regions of electron density (two bonding pairs and two lone pairs), which gives it a tetrahedral electron geometry.
However, the actual molecular shape depends only on the position of the atoms, not the lone pairs. The two lone pairs on sulfur push the bonded fluorine atoms closer together. As a result, the molecule takes on a bent molecular geometry, similar to that of water (H₂O), which also has two lone pairs.
The bond angle in SF₂ is slightly less than the ideal tetrahedral angle of 109.5 degrees, typically around 98 to 100 degrees, due to increased repulsion from the lone pairs.
This bent shape means the molecule is polar because the dipole moments of the S–F bonds do not cancel out. Fluorine is more electronegative than sulfur, pulling electron density toward itself. The asymmetry from the bent shape ensures that the molecule has a net dipole moment, making SF₂ a polar molecule.
In summary, SF₂ has a bent molecular geometry with tetrahedral electron geometry caused by two lone pairs on the central sulfur atom.
