Bond Angle

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

Moderators: Chem_Mod, Chem_Admin

Verity Lai 2K
Posts: 100
Joined: Sat Aug 24, 2019 12:18 am

Bond Angle

Postby Verity Lai 2K » Thu Nov 14, 2019 3:00 pm

Could someone remind me what the bond angles are for each VSEPR shape?? Thanks!

Alexis Webb 2B
Posts: 124
Joined: Thu Jul 11, 2019 12:15 am

Re: Bond Angle

Postby Alexis Webb 2B » Thu Nov 14, 2019 3:06 pm

180 degrees for linear,
120 degrees for trigonal planar, 109.5 degrees for tetrahedral, 120 degrees for the trigonal bond angles and 90 and 180 degrees for the axial bond angles in a trigonal bipyramidal, 90 and 180 degrees for octahedral

Ziyan Wang 3J
Posts: 51
Joined: Wed Sep 18, 2019 12:22 am

Re: Bond Angle

Postby Ziyan Wang 3J » Thu Nov 14, 2019 3:08 pm

Linear: 180
Trigonal planar: 120
Tetrahedral: 109.5
Trigonal bipyramidal: trigonal bond angle: 120, axial bond angle: 90 and 180
Octahedral: 90 and 180

JasonLiu_2J
Posts: 109
Joined: Sat Aug 24, 2019 12:17 am

Re: Bond Angle

Postby JasonLiu_2J » Thu Nov 14, 2019 3:12 pm

This is a very broad question since there are many, many VSEPR shapes depending on different combinations of numbers of bonding pairs and lone pairs on the central atom. However, for the basic structures with no lone pairs, they are as follows:
2 atoms attached to central atom = linear = 180 degrees between the two attached atoms
3 atoms attached to central atom = trigonal planar = 120 degrees each between the 3 atoms
4 atoms attached to central atom = tetrahedral = 109.5 degrees each between the 4 atoms
5 atoms attached to central atom = trigonal bipyramidal = 90 degrees between those on vertical versus horizontal plane, 180 degrees between the two on the vertical plane, and 120 degrees between the 3 on the horizontal plane. (Imagine a trigonal planar with a linear vertically through the middle)
6 atoms attached to central atom = octahedral = 90 degrees between those on vertical plane versus horizontal plane, 90 degrees between the 4 atoms on the horizontal plane, and 180 degrees between the two on the vertical plane. (imagine a square planar with a linear vertically through the middle)
Keep in mind that these bond angles are only for when the atoms around the central atom are of the same element. They will be slightly different if the elements of the atoms are different due to different repulsions.
Hope this helps!


Return to “Determining Molecular Shape (VSEPR)”

Who is online

Users browsing this forum: No registered users and 1 guest