Answer:
Trigonal planar, square planar, bent, and T-shaped
Explanation:
The answer comes from VSEPR theory.
The molecules with a planar shape are those with general formula AX₃, AX₂E₂, AX₃E₂, and AX₄E₂, where A is the central atom, X are the directly attached atoms, and E are lone pairs.
Here are some examples.
AX₃ molecules
AX₃ molecules have three bonding pairs and no lone pairs.
An example is BF₃.
Its molecular shape is trigonal planar.
AX₂E₂ Molecules
AX₂E₂ molecules have two bonding pairs and two lone pairs.
An example is H₂O.
The electron geometry is tetrahedral.
However, we do not count the lone pairs in determining the molecular shape, so the molecule is bent.
AX₃E₂ molecules
AX₃E₂ molecules have three bonding pairs and no lone pairs.
An example is ClF₃.
The electron geometry is trigonal bipyramidal.
The molecule is T-shaped.
AX₄E₂ molecules
AX₄E₂ molecules have three bonding pairs and no lone pairs.
An example is XeF₄.
The electron geometry is octahedral.
The molecule is square planar.
