What is the molecular geometry of the XeF_4 molecule?

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

Answer: (D)

Verified step by step guidance

1. Step 1: Determine the Lewis structure of XeF_4. Xenon (Xe) is the central atom bonded to four fluorine (F) atoms. Count the total valence electrons: Xe has 8 valence electrons, each F has 7, so total electrons = 8 + 4 \times 7 = 36 electrons.
2. Step 2: Arrange the four fluorine atoms around the xenon atom and distribute the electrons to satisfy the octet rule for fluorine atoms. After bonding, place the remaining electrons as lone pairs on the xenon atom.
3. Step 3: Count the regions of electron density (bonding and lone pairs) around the central atom. XeF_4 has 4 bonding pairs and 2 lone pairs, making a total of 6 electron pairs.
4. Step 4: Use VSEPR theory to predict the electron pair geometry. Six electron pairs around the central atom correspond to an octahedral electron geometry.
5. Step 5: Consider the positions of the lone pairs. Lone pairs occupy positions opposite each other to minimize repulsion, resulting in a square planar molecular geometry for XeF_4.