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3. Predict the ideal bond angle and any deviation based on electron- group arrangement and the presence of lone pairs or multiple bonds.
Solution: (a) For PF 3 .
1. Write the Lewis structure:
4. Draw and name the molecular shape by counting bonding groups and non-bonding groups separately.
Predicting Molecular Shapes with 2, 3, and 4 Electron Groups
Problem: Determine the molecular shape and ideal bond angles of (a) PF 3 and (b) COCl 2
2. Assign the electron-group arrangement: 4 electron groups around P (three bonding and one lone pair) give the tetrahedral arrangement.
3. For the tetrahedral arrangement, the ideal angle is 109.5°. With one lone pair, the actual bond angle should be less than 109.5°.
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