VSEPR Theory (Molecular Shapes)

Vocabulary flashcards generated from lecture notes on VSEPR theory, molecular shapes, electron geometries, hybridizations, and bond angles.

VSEPR Theory Symbol $A$

The central atom in a VSEPR generic formula.

VSEPR Theory Symbol $X$

An atom bonded to central atom $A$.

VSEPR Theory Symbol $E$

A lone pair on central atom $A$.

VSEPR Theory Domain Focus Rule

The rule that only electron densities or domains around central atom $A$ are considered, ignoring lone pairs on $X$ or other atoms.

Generic Formula $AX$

Represents a molecule with $1$ domain ($1$ bonded atom, $0$ lone pairs), linear molecular shape, linear electron geometry, $s$ hybridization, bond angle of $180^\text{o}$, and example $HF$.

Generic Formula $AX_2$

Represents a molecule with $2$ domains ($2$ bonded atoms, $0$ lone pairs), linear molecular shape, linear electron geometry, $sp$ hybridization, bond angle of $180^\text{o}$, and example $CO_2$.

Generic Formula $AXE$

Represents a molecule with $2$ domains ($1$ bonded atom, $1$ lone pair), linear molecular shape, linear electron geometry, $sp$ hybridization, bond angle of $180^\text{o}$, and example CN^-1

Generic Formula $AX_3$

Represents a molecule with $3$ domains ($3$ bonded atoms, $0$ lone pairs), trigonal planar molecular shape, trigonal planar electron geometry, $sp^2$ hybridization, bond angle of $120^\text{o}$, and example $HBCl_2$.

Generic Formula $AX_2E$

Represents a molecule with $3$ domains ($2$ bonded atoms, $1$ lone pair), bent molecular shape, trigonal planar electron geometry, $sp^2$ hybridization, bond angle of $120^\text{o}$, and example $SnCl_2$.

Generic Formula $AXE_2$

Represents a molecule with $3$ domains ($1$ bonded atom, $2$ lone pairs), linear molecular shape, trigonal planar electron geometry, $sp^2$ hybridization, bond angle of $120^\text{o}$, and example $O_2$.

Generic Formula $AX_4$

Represents a molecule with $4$ domains ($4$ bonded atoms, $0$ lone pairs), tetrahedral molecular shape, tetrahedral electron geometry, $sp^3$ hybridization, bond angle of $109.5^\text{o}$, and example $SiCl_4$.

Generic Formula $AX_3E$

Represents a molecule with $4$ domains ($3$ bonded atoms, $1$ lone pair), trigonal pyramidal molecular shape, tetrahedral electron geometry, $sp^3$ hybridization, bond angle of $109.5^\text{o}$, and example $PH_3$.

Generic Formula $AX_2E_2$

Represents a molecule with $4$ domains ($2$ bonded atoms, $2$ lone pairs), bent molecular shape, tetrahedral electron geometry, $sp^3$ hybridization, bond angle of $109.5^\text{o}$, and example $SeBr_2$.

Generic Formula $AXE_3$

Represents a molecule with $4$ domains ($1$ bonded atom, $3$ lone pairs), linear molecular shape, tetrahedral electron geometry, $sp^3$ hybridization, bond angle of $109.5^\text{o}$, and example $Cl_2$.