Which of the following best describes the molecular geometry of OCl_2 (dichlorine monoxide)?

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

Answer: (B)

Verified step by step guidance

1. Step 1: Determine the Lewis structure of OCl_2 by counting the total valence electrons. Oxygen has 6 valence electrons, and each chlorine has 7, so total valence electrons = 6 + 2 × 7 = 20 electrons.
2. Step 2: Draw the skeletal structure with oxygen as the central atom bonded to two chlorine atoms. Place single bonds between oxygen and each chlorine, using 4 electrons (2 bonds × 2 electrons each).
3. Step 3: Distribute the remaining electrons to satisfy the octet rule. Place lone pairs on the chlorine atoms first, then place remaining electrons as lone pairs on oxygen.
4. Step 4: Count the regions of electron density around the central oxygen atom. There are two bonding pairs (O–Cl bonds) and two lone pairs on oxygen, totaling four regions of electron density.
5. Step 5: Use VSEPR theory to determine the molecular geometry. Four regions of electron density correspond to a tetrahedral electron geometry, but with two lone pairs, the molecular shape is bent (angular).