Which of the following best describes the molecular geometry of NF3?

• A. Tetrahedral
• B. Bent
• C. Trigonal planar
• D. Trigonal pyramidal

Answer: (D)

Verified step by step guidance

1. Determine the Lewis structure of NF\_3 by counting the total valence electrons: nitrogen has 5 valence electrons, and each fluorine has 7, so total electrons = 5 + 3 \times 7 = 26 electrons.
2. Draw the Lewis structure with nitrogen as the central atom bonded to three fluorine atoms, and place the remaining electrons as lone pairs to satisfy the octet rule for each atom.
3. Count the regions of electron density (bonding and lone pairs) around the central nitrogen atom. There are three bonding pairs (N-F bonds) and one lone pair on nitrogen, making a total of four regions.
4. Use the VSEPR theory to predict the molecular geometry: four regions of electron density correspond to a tetrahedral electron geometry, but because one region is a lone pair, the molecular shape is trigonal pyramidal.
5. Confirm that the molecular geometry is trigonal pyramidal, which matches the correct answer, rather than tetrahedral, bent, or trigonal planar.