Which of the following best describes the molecular geometry of SO_2?

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

Answer: (A)

Verified step by step guidance

1. Identify the central atom in the molecule SO\_2, which is sulfur (S).
2. Determine the total number of valence electrons for SO\_2 by adding the valence electrons of sulfur and oxygen atoms. Sulfur has 6 valence electrons, and each oxygen has 6 valence electrons, so total valence electrons = 6 + 2 \times 6 = 18.
3. Draw the Lewis structure of SO\_2, placing sulfur in the center with two oxygen atoms bonded to it. Distribute the remaining electrons to satisfy the octet rule for each atom, considering possible resonance structures.
4. Count the regions of electron density (bonding and lone pairs) around the central sulfur atom. SO\_2 has two bonding regions (two S-O bonds) and one lone pair on sulfur, making a total of three regions of electron density.
5. Use the VSEPR theory to determine the molecular geometry based on the electron regions. Three regions with one lone pair correspond to a 'bent' molecular geometry, as lone pairs repel more strongly and distort the shape from trigonal planar to bent.