polarity of shapes

[Savannah Mance 4G]

Are molecules that are trigonal planar usually non polar?

[Rodrigo2J]

The molecule will be non polar as long as it doesn't have a net dipole moment. So as long as the three atoms around the central atom are the same then yes it should be non polar for a trigonal planar geometry.

[Nawal Dandachi 1G]

only if they are symmetric and all the atoms attached to the central atom are the same; however, if the atoms attached to the central atom are not the same, then it is polar.

[sarahsalama2E]

Also, remember that typically shapes that have lone pairs are usually always polar even if all the attached atoms are the same; however AX4E2, square planar, is an exception to that rule because it becomes nonpolar because the dipole moments cancel. You can see this if you draw the 3-D shape.