What is the electron geometry of SF_4?

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

Answer: (C)

Verified step by step guidance

1. Identify the central atom in SF_4, which is sulfur (S).
2. Determine the total number of valence electrons around sulfur: sulfur has 6 valence electrons, and each fluorine contributes 1 electron, so total valence electrons = 6 + 4 = 10 pairs of electrons (or 20 electrons).
3. Count the number of bonding pairs and lone pairs on sulfur: SF_4 has 4 bonding pairs (one for each S-F bond) and 1 lone pair on sulfur.
4. Use the VSEPR (Valence Shell Electron Pair Repulsion) theory to predict the electron geometry. With 4 bonding pairs and 1 lone pair, the electron geometry corresponds to a trigonal bipyramidal arrangement to minimize repulsions.
5. Conclude that the electron geometry of SF_4 is trigonal bipyramidal, even though the molecular shape (considering only atoms) is seesaw due to the lone pair.