Chp. 9: Molecular Shapes

Molecular shape is determined by bond angles and bond:

length

Molecular shape is determined by bond length and bond:

angles

Electron pairs ___ each other.

repel

VSEPR

Valance-shell Electron-pair Repulsion Model

_SEPR Model

valence

V_EPR Model

shell

VS_PR Model

electron

VSE_R Model

Pair

VSEP_ Model

repulsion

Every bond or lone pair on a central atom represents a new:

electron domain

Electron-Domain Geometry: Linear

2 electron domains

Electron-Domain Geometry: Trigonal planar

3 electron domains

Electron-Domain Geometry:Tetrahedral

4 electron domains

Electron-Domain Geometry: trigonal bipyramidal

5 electron domains

Electron-Domain Geometry: octahedral

6 electron domains

Case where Electron-Domain Geometry equals Molecular Geometry

linear

Electron-Domain Geometry (Trigonal planar) if all electron domains are bonding

Molecular Geometry: Trigonal planar

Electron-Domain Geometry (Trigonal planar) if all one electron domain is nonbonding and two electron domains are bonding

Molecular Geometry: bent

Electron Domain Geometry (Tetrahedral) if all domains are bonding

Molecular Geometry (Tetrahedral): tetrahedral

Electron Domain Geometry (Tetrahedral) if there are 3 bonding domains and 1 nonbonding domain

Molecular Geometry (Tetrahedral): Trigonal pyramidal

Electron Domain Geometry (Tetrahedral) if there are 2 bonding domains and 2 nonbonding domains

Molecular Geometry (Tetrahedral): bent

Nonbonding pairs are physically ____ than bonding pairs.

larger

Nonbonding pairs are physically larger than bonding pairs. Therefore, their repulsions are:

greater

Double and triple bonds have ____ electron domains than single bonds.

larger

There are two distinct positions for the Trigonal Bipyramidal Electron Geometry (5 electron domains):

axial & equatorial

In Trigonal Bipyramidal Electron Geometry, lone pairs occupy ____ positions.

equatorial

There are four distinct molecular geometries for Trigonal Bipyramidal Geometry (5), including: trigonal bipyramidal…

seesaw, t-shaped, and linear

5 Trigonal Bipyramidal Electron Domain Geometry: 5 bonding domains

Molecular Geometry: trigonal bipyramidal

5 Trigonal Bipyramidal Electron Domain Geometry- 4:1

seesaw

5 Trigonal Bipyramidal Electron Domain Geometry: 3:2

t-shaped

5 Trigonal Bipyramidal Electron Domain Geometry: 2:3

linear

There are three molecular geometries for Octahedral Electron Geometry: octahedral…

square pyramidal, and square planar

Octahedral (6) Electron Geometry: 5:1

square pyramidal

Octahedral (6) Electron Geometry: 4:2

square planar

In the space-filling model, what determines the relative sizes of the spheres?

atomic radii

Linear (2) predicted bond angles

180

Trigonal planar (3) predicted bond angles

120

Tetrahedral (4) predicted bond angles

109.5

Trigonal bipyramidal (5) predicted bond angles

120, 90

Octahedral (6) bond angles

90

linear hybridization

sp

trigonal planar

sp²

tetrahedral

sp³