What is the electron geometry of XeF_4?

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

Answer: (C)

Verified step by step guidance

1. Identify the central atom and its valence electrons. Xenon (Xe) is the central atom, and it belongs to group 18, so it has 8 valence electrons.
2. Count the electrons contributed by the surrounding atoms. Each fluorine (F) atom contributes 1 electron for bonding. Since there are 4 fluorine atoms, that adds 4 electrons.
3. Calculate the total number of valence electrons around the central atom: 8 (from Xe) + 4 (from 4 F atoms) = 12 electrons, or 6 electron pairs.
4. Determine the number of bonding pairs and lone pairs on the central atom. There are 4 bonding pairs (one for each Xe-F bond) and 2 lone pairs (since 6 pairs total - 4 bonding = 2 lone pairs).
5. Use the VSEPR theory to predict the electron geometry. With 6 electron pairs (4 bonding + 2 lone pairs), the electron geometry is octahedral, even though the molecular shape (based on atoms only) is square planar.