What is the electron geometry of SBr_4?

• A. Trigonal bipyramidal
• B. Square planar
• C. Octahedral
• D. Tetrahedral

Answer: (A)

Verified step by step guidance

1. Determine the total number of valence electrons for the central atom sulfur (S). Sulfur is in group 16, so it has 6 valence electrons.
2. Count the number of atoms bonded to sulfur. In SBr_4, sulfur is bonded to 4 bromine atoms.
3. Calculate the total number of electron regions (bonding and lone pairs) around sulfur. Since sulfur has 6 valence electrons and forms 4 bonds, it uses 4 electrons for bonding, leaving 2 electrons (1 lone pair) on sulfur. Therefore, there are 5 regions of electron density (4 bonding pairs + 1 lone pair).
4. Use the VSEPR theory to determine the electron geometry based on 5 regions of electron density. According to VSEPR, 5 electron regions correspond to a trigonal bipyramidal electron geometry.
5. Note that the presence of one lone pair affects the molecular shape but not the electron geometry. The molecular shape of SBr_4 is 'see-saw', but the electron geometry remains trigonal bipyramidal.