trigonal planar vs. t-shaped

[Emma Li 2C]

How do you tell if a molecule (with 4 atoms) has a trigonal planar shape or is t-shaped?

[Sammy Thatipelli 1B]

an atom is trigonal planar if it has three regions of electron density and the angles are at 120 degrees evenly, like an equilateral triangle. it is t-shaped if you have three regions of electron density, but one of these regions consists of a lone pair of electrons. the lone pair electrons cause the molecule to have angles to be slightly less than 120 degrees

[Tatiana R Dis 3E]

If it has three reactions of density but one is a lone pair, wouldn’t that be bent?

[aTirumalai-1I]

Nope, a molecule with 4 regions of electron density, 2 bonded and 2 lone pairs, would be bent.

[Justin Yu 3H]

First off, although trigonal planar and t-shaped molecules both consist of 4 atoms, they differ in the amount of electron pairs on the central atom. Trigonal planar molecules have 4 electron pairs, 1 lone and 3 pairs with the other 3 atoms, while t-shaped molecules have 5 electron pairs, 2 lone and 3 pairs with the other 3 atoms.

[Nickolas Manipud 1C]

How do you tell if a molecule (with 4 atoms) has a trigonal planar shape or is t-shaped?

I was having trouble with this too but this picture really helps
https://goo.gl/images/2yK9vp