## Multiple different bond angles

(Polar molecules, Non-polar molecules, etc.)

KylieY_3B
Posts: 31
Joined: Fri Sep 28, 2018 12:24 am

### Multiple different bond angles

Why do some structures have bond angles of different degrees? For example, in my discussion section we used the example of TeCl4 as having angles of both 120 degrees and 90 degrees. Also, how do we determine when this is the case?

Germar G 4F
Posts: 38
Joined: Fri Sep 28, 2018 12:28 am

### Re: Multiple different bond angles

TeCl4 has different bond angles because of its molecular geometry. It has seesaw geometry, since it has 4 single bonds and one lone pair. All seesaw geometries will have 90, 120, and 180 degree angles in their 3-D shape. If you look at a picture of "seesaw geometry" you can see each of the angles.

KylieY_3B
Posts: 31
Joined: Fri Sep 28, 2018 12:24 am

### Re: Multiple different bond angles

Germar G 4F wrote:TeCl4 has different bond angles because of its molecular geometry. It has seesaw geometry, since it has 4 single bonds and one lone pair. All seesaw geometries will have 90, 120, and 180 degree angles in their 3-D shape. If you look at a picture of "seesaw geometry" you can see each of the angles.

Thank you! Is the easiest way to determine bond angles simply to memorize it in accordance with the shape?

whitney_2C
Posts: 74
Joined: Fri Sep 28, 2018 12:28 am

### Re: Multiple different bond angles

If you click on this link you can download a software that shows molecules in 3D and you can move them around so you have a better idea of the shapes and angles! If that doesn't help you with remembering molecule bond angles for different shapes then I would just memorize them.

whitney_2C
Posts: 74
Joined: Fri Sep 28, 2018 12:28 am

### Re: Multiple different bond angles

KylieY_3B
Posts: 31
Joined: Fri Sep 28, 2018 12:24 am

### Re: Multiple different bond angles

whitneyh_4_4G wrote:If you click on this link you can download a software that shows molecules in 3D and you can move them around so you have a better idea of the shapes and angles! If that doesn't help you with remembering molecule bond angles for different shapes then I would just memorize them.

Wow! Thank you!

uhedlund
Posts: 38
Joined: Wed Nov 15, 2017 3:03 am

### Re: Multiple different bond angles

Yes, having different molecular geometry results in the angles between different atoms being different sizes. Lone pairs can play a role in this geometry.