What is the molecular geometry of XeCl_4?

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

Answer: (C)

Verified step by step guidance

1. Step 1: Determine the total number of valence electrons for the central atom, xenon (Xe). Xenon is a noble gas with 8 valence electrons.
2. Step 2: Count the electrons contributed by the surrounding atoms. Each chlorine (Cl) atom contributes 7 valence electrons, but since they form bonds, focus on the bonding pairs. For XeCl_4, there are 4 Cl atoms bonded to Xe, so 4 bonding pairs.
3. Step 3: Calculate the total number of electron pairs around the central atom by adding bonding pairs and lone pairs. Xenon can expand its octet, so after forming 4 bonds, determine how many lone pairs remain on Xe.
4. Step 4: Use the VSEPR (Valence Shell Electron Pair Repulsion) theory to predict the molecular geometry. The arrangement of electron pairs (bonding and lone pairs) around Xe determines the shape. For 4 bonding pairs and 2 lone pairs, the electron geometry is octahedral, but the molecular geometry (shape) is different.
5. Step 5: Identify the molecular geometry by considering only the positions of atoms (bonding pairs). With 4 bonded atoms and 2 lone pairs opposite each other, the molecular geometry is square planar.