What are the shape and bond angle of a water molecule?
Answer and explanation
Correct answer: B. Bent, 104.5 degrees
- Step 1: Oxygen has two bonding pairs and two lone pairs. Step 2. Lone pairs repel more strongly than bonding pairs, squeezing the angle below 109.5 degrees to 104.5 degrees. Answer: Bent, 104.5 degrees. Why not the others: linear would need no lone pairs and two bonds; trigonal planar has three bonding pairs; 109.5 degrees ignores the extra lone pair repulsion.
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