determine the correct molecular geometry based on the number of bonds and lone pairs around the central…
determine the correct molecular geometry based on the number of bonds and lone pairs around the central atom.\n• bent\n• tetrahedral\n• trigonal planar\n• trigonal pyramidal\nbonds lone pairs geometry\n2 2 click for list bent\n3 0 tetrahedral trigonal planar\n3 1 trigonal pyramidal\n4 0 click for list
Answer
Explanation:
Step1: Recall VSEPR rules
The valence - shell electron - pair repulsion (VSEPR) theory is used to predict molecular geometries based on the number of bonding pairs and lone pairs around the central atom.
Step2: Analyze case of 2 bonds and 2 lone pairs
When there are 2 bonds and 2 lone pairs around the central atom, the electron - pair geometry is tetrahedral, but the molecular geometry is bent due to the repulsion of the lone pairs.
Step3: Analyze case of 3 bonds and 0 lone pairs
When there are 3 bonds and 0 lone pairs around the central atom, the electron - pair geometry and molecular geometry are trigonal planar as the electron groups are arranged to minimize repulsion in a plane with 120 - degree bond angles.
Step4: Analyze case of 3 bonds and 1 lone pair
When there are 3 bonds and 1 lone pair around the central atom, the electron - pair geometry is tetrahedral, but the molecular geometry is trigonal pyramidal because the lone pair occupies more space and repels the bonding pairs.
Step5: Analyze case of 4 bonds and 0 lone pairs
When there are 4 bonds and 0 lone pairs around the central atom, the electron - pair geometry and molecular geometry are tetrahedral with bond angles of approximately 109.5 degrees.
Answer:
| Bonds | Lone pairs | Geometry |
|---|---|---|
| 2 | 2 | Bent |
| 3 | 0 | Trigonal planar |
| 3 | 1 | Trigonal pyramidal |
| 4 | 0 | Tetrahedral |