Which shapes to memorize

[Stacey Phan 2I]

I was wondering if someone could tell me all the shapes we should memorize with their description?

[BrittneyMyint1D]

I'm assuming it's all the shapes that Dr. Lavelle mentioned in the lectures:
- linear: central atom has 2 bonding pairs; 180 degree bond angle
- trigonal planar: central atom has 3 bonding pairs, 120 degree bond angles
- tetrahedral: central atom has 4 bonding pairs, 109.5 degree bond angle
- trigonal bipyramidal: central atom has 5 bonding pairs, trigonal bond angles 120 degrees and axial bond angles 90 and 180 degrees
- octahedral: central atom has 6 bonding pairs, bond angles are 90 and 180 degrees
- trigonal pyramidal: central atom has 3 bonding pairs and 1 lone pair (arranged tetrahedrally but 3/4 positions are occupied by atoms)
- bent/angular: central atom has 2 lone pairs and 2 bonding pairs
- seesaw: central atom has 4 bonding pairs and 1 lone pair
- square planar: central atom has 4 bonding pairs and 2 lone pairs

May have missed a couple of details but hope this helped!

[KatarinaReid_3H]

I would recommend googling a lookup table as well as there is sort of a pattern to the molecular shapes.
Electron groups: 2, Bonding Groups: 2, Lone Pairs: 0 = Linear

Electron groups: 3, Bonding Groups: 3, Lone Pairs: 0 = Trigonal Planar

Electron groups: 3, Bonding Groups: 2, Lone Pairs: 1 = Bent

Electron groups: 4, Bonding Groups: 4, Lone Pairs: 0 = Tetrahedral

Electron groups: 4, Bonding Groups: 3, Lone Pairs: 1 = Trigonal Pyramidal

Electron groups: 4, Bonding Groups: 2, Lone Pairs: 2 = Bent

Electron groups: 5, Bonding Groups: 5, Lone Pairs: 0 = Trigonal Bipyramidal

Electron groups: 5, Bonding Groups: 4, Lone Pairs: 1 = Seesaw

Electron groups: 5, Bonding Groups: 3, Lone Pairs: 2 = T-Shaped

Electron groups: 5, Bonding Groups: 2, Lone Pairs: 3 = Linear

Electron groups: 6, Bonding Groups: 6, Lone Pairs: 0 = Octahedral

Electron groups: 6, Bonding Groups: 5, Lone Pairs: 1 = Square Pyramidal

Electron groups: 6, Bonding Groups: 4, Lone Pairs: 2 = Square Planar

[Inderpal Singh 2L]

Would we have to memorize the bond angles as well?

[Mahika More 1H]

Would we have to memorize the bond angles as well?

I don't think we would have to memorize bond angles for each one but you should know the general idea about how each shape looks and be able to deduce from there what the values of the angles are around (for example 90 vs less than 90 degrees).

[darchen3G]

Here is a good image from sapling that has the shapes

If it won't load here's the link: https://i.imgur.com/HrydyqN.png

[Mahnoor_Wani_1I]

If you are struggling with memorizing the molecular shapes, watch this video: https://www.youtube.com/watch?v=r2XmaiEC0Vw!

[Stacey Phan 2I]

I'm assuming it's all the shapes that Dr. Lavelle mentioned in the lectures:
- linear: central atom has 2 bonding pairs; 180 degree bond angle
- trigonal planar: central atom has 3 bonding pairs, 120 degree bond angles
- tetrahedral: central atom has 4 bonding pairs, 109.5 degree bond angle
- trigonal bipyramidal: central atom has 5 bonding pairs, trigonal bond angles 120 degrees and axial bond angles 90 and 180 degrees
- octahedral: central atom has 6 bonding pairs, bond angles are 90 and 180 degrees
- trigonal pyramidal: central atom has 3 bonding pairs and 1 lone pair (arranged tetrahedrally but 3/4 positions are occupied by atoms)
- bent/angular: central atom has 2 lone pairs and 2 bonding pairs
- seesaw: central atom has 4 bonding pairs and 1 lone pair
- square planar: central atom has 4 bonding pairs and 2 lone pairs

May have missed a couple of details but hope this helped!

This is extremely helpful thank you!!

[Stacey Phan 2I]

I would recommend googling a lookup table as well as there is sort of a pattern to the molecular shapes.
Electron groups: 2, Bonding Groups: 2, Lone Pairs: 0 = Linear

Electron groups: 3, Bonding Groups: 3, Lone Pairs: 0 = Trigonal Planar

Electron groups: 3, Bonding Groups: 2, Lone Pairs: 1 = Bent

Electron groups: 4, Bonding Groups: 4, Lone Pairs: 0 = Tetrahedral

Electron groups: 4, Bonding Groups: 3, Lone Pairs: 1 = Trigonal Pyramidal

Electron groups: 4, Bonding Groups: 2, Lone Pairs: 2 = Bent

Electron groups: 5, Bonding Groups: 5, Lone Pairs: 0 = Trigonal Bipyramidal

Electron groups: 5, Bonding Groups: 4, Lone Pairs: 1 = Seesaw

Electron groups: 5, Bonding Groups: 3, Lone Pairs: 2 = T-Shaped

Electron groups: 5, Bonding Groups: 2, Lone Pairs: 3 = Linear

Electron groups: 6, Bonding Groups: 6, Lone Pairs: 0 = Octahedral

Electron groups: 6, Bonding Groups: 5, Lone Pairs: 1 = Square Pyramidal

Electron groups: 6, Bonding Groups: 4, Lone Pairs: 2 = Square Planar

Thank you so much I will definitely be using this to study!

[Anastasia Yulo 1C]

I studies the shapes that he shared on lecture and tried my best to understand them conceptually so that I could understand them:Trigonal Planar, tetrahedral, trigonal bipyramidal, octahedral, trigonal pyramidal, see-saw, square planar. Once I recognized the pattern in the repulsions, it helped me memorize the angles characteristic to each shape. This table is an extremely helpful, organized visual: https://data.templateroller.com/pdf_doc ... nt_big.png

[Madison Muggeo 3H]

https://d20ohkaloyme4g.cloudfront.net/i ... 0_1697.png
Is the table that I memorized, it is really useful.

[Kaitlyn Hernandez 3I]

Here's another helpful document that I've been using to help me study molecular shape!

https://www.angelo.edu/faculty/kboudrea ... _VSEPR.pdf