Which of the following best describes the Lewis dot structure of XeBr2Cl2?

• A. Xe is the central atom with two Br and two Cl atoms bonded to it, and one lone pair on Xe, resulting in a trigonal bipyramidal geometry.
• B. Xe is the central atom with one Br and three Cl atoms bonded to it, and one lone pair on Xe, resulting in a seesaw geometry.
• C. Xe is the central atom with two Br and two Cl atoms bonded to it, and no lone pairs on Xe, resulting in a tetrahedral geometry.
• D. Xe is the central atom with two Br and two Cl atoms bonded to it, and two lone pairs on Xe, resulting in a square planar geometry.

Answer: (D)

Verified step by step guidance

1. Identify the central atom in the molecule, which is Xenon (Xe) because it is the least electronegative and can expand its octet due to being a noble gas in period 5.
2. Count the total number of valence electrons: Xe has 8 valence electrons, each Br has 7, and each Cl has 7. For XeBr2Cl2, calculate total valence electrons as 8 + 2×7 + 2×7.
3. Determine the number of electron pairs around Xe by dividing the total valence electrons by 2, then subtract the bonding pairs (4 bonds to halogens) to find the number of lone pairs on Xe.
4. Use the VSEPR theory to predict the molecular geometry: with 4 bonded atoms and 2 lone pairs, the electron pair geometry is octahedral, but the molecular shape (considering only atoms) is square planar.
5. Confirm that the Lewis structure has Xe at the center bonded to two Br and two Cl atoms, with two lone pairs on Xe, resulting in a square planar geometry.