What is the approximate Cl–Xe–Cl bond angle in the molecule XeCl_4?

• A. 120^ext{o}
• B. 90^ext{o}
• C. 180^ext{o}
• D. 109.5^ext{o}

Answer: (B)

Verified step by step guidance

1. Identify the central atom and the surrounding atoms in the molecule XeCl_4. Xenon (Xe) is the central atom bonded to four chlorine (Cl) atoms.
2. Determine the total number of valence electrons for XeCl_4 by adding the valence electrons of xenon and chlorine atoms. Xenon has 8 valence electrons, and each chlorine has 7 valence electrons.
3. Use the VSEPR (Valence Shell Electron Pair Repulsion) theory to predict the molecular geometry. Consider both bonding pairs and lone pairs on the central atom. Xenon in XeCl_4 has 4 bonding pairs and 2 lone pairs.
4. Based on VSEPR theory, a molecule with 4 bonding pairs and 2 lone pairs around the central atom adopts an octahedral electron geometry but a square planar molecular shape. Lone pairs occupy axial positions, minimizing repulsion.
5. In a square planar geometry, the bond angles between the chlorine atoms are 90° and 180°, so the approximate Cl–Xe–Cl bond angle is 90°.