T shaped

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Peter Nguyen 2I
Posts: 61
Joined: Fri Sep 28, 2018 12:29 am

T shaped

Postby Peter Nguyen 2I » Mon Nov 26, 2018 5:22 pm

Why does AX3E2 make a T-shape and doesn't form a trigonal planar shape?

Rehan Chinoy 1K
Posts: 67
Joined: Fri Sep 28, 2018 12:25 am

Re: T shaped

Postby Rehan Chinoy 1K » Mon Nov 26, 2018 5:25 pm

I believe it has to do with the bond angles. The two lone pairs cause the angles between the central atom and each ligand to be less than 90 degrees, whereas the angles between the ligands and the central atom in a trigonal planar molecule are 120 degrees.

Elena Maneffa 1E
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Joined: Fri Sep 28, 2018 12:27 am
Been upvoted: 1 time

Re: T shaped

Postby Elena Maneffa 1E » Mon Nov 26, 2018 11:05 pm

AX3E2 means that an atom is bonded to 3 other atoms and also has 2 lone pairs.

If it had just one lone pair it would be trigonal pyramidal but because of the second lone pair, it changes the angles and is now considered to be T-shaped.

Matthew Mar 1J
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Joined: Fri Sep 28, 2018 12:15 am
Been upvoted: 1 time

Re: T shaped

Postby Matthew Mar 1J » Tue Nov 27, 2018 11:47 am

The T-shape is a planar shape, so you can think of it almost like a trigonal planar shape that just has two lone pairs which push the atoms closer together to a 90 degree angle instead of the 120 degree angle.

Mayaal_Khan_4H
Posts: 41
Joined: Fri Sep 28, 2018 12:28 am

Re: T shaped

Postby Mayaal_Khan_4H » Tue Nov 27, 2018 1:16 pm

AX3E2 means that the central atom is bonded to 3 atoms and has 2 lone pairs, since there are 2 lone pairs instead of 1, the bond angles change and therefore the shape changes from trigonal planar to T-shape

Adrienne_4F
Posts: 64
Joined: Fri Sep 28, 2018 12:27 am

Re: T shaped

Postby Adrienne_4F » Tue Nov 27, 2018 1:29 pm

There is repulsion due to the two lone pairs, therefore they will push the atoms closer together, making a T shape rather than a trigonal planar.

905096106
Posts: 30
Joined: Fri Oct 05, 2018 12:17 am

Re: T shaped

Postby 905096106 » Tue Nov 27, 2018 1:34 pm

It is not trigonal planar because of the additional two lone pairs. These distort the shape and make the bond angles smaller so the 120 degree angle found on trigonal planar shapes is not obtained.


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