Key Terms Chapter 9 Mia Carlos Period 1

Hybridization Definition:a mixing of the native orbitals on a given atom to form special atomic orbitals for bonding.

Sp 3 Hybridization Definition:four effective bonding pairs around the central atom- tetrahedral geometry Example: methane

Hybrid orbitals Definition:a set of atomic orbitals adopted by an atom in a molecule different from those of the atom in the free state.

Sp 2 Hybridization Definition:- four effective bonding pairs around the central atom- tetrahedral geometry Example : ethylene (C 2 H 4 )

Sigma (σ) bond Definition: a covalent bond in which the electron pair is shared in an area centered on a line running between the atoms.

Pi Bond Definition: a covalent bond in which parallel p orbitals share an electron pair occupying the space above and below the line joining the atoms.

Sp Hybridization Definition:- two effective pairs around the central atom- 180 degree angle - linear geometry examples include carbon dioxide and nitrogen (N 2 )

Dsp 3 Hybridization Definition:five effective pairs around the central atom resulting in a trigonal bipyramidal arrangement examples include PCl 5 and I 3 -

D 2 sp 3 Hybridization Definition:six effective pairs surround central atom resulting in an octahedral geometry example : SF 6 and XeF 4

Molecular orbital model Definition:a model that regards a molecule as a collection of nuclei and electrons, where the electrons are assumed to occupy orbitals much as they do in atoms, but having the orbitals extend over the entire molecule. In this model the electrons are assumed to be de localized rather than always located between a given pair of atoms.

Molecular orbital (MO) Definition:solution s to the molecular problem that can hold two electrons with opposite spins that the square of the molecular orbital wave function indicates electron probability.

Sigma molecular orbital Definition:When these bonding orbitals are occupied by a pair of electron

Bonding molecular orbital Definition:an orbital lower in energy than the atomic orbitals of which it is composed.  -----Bonding molecular orbital

Anti bonding molecular orbital Definition:an orbital higher in energy than the atomic orbitals of which it is composed.  --Anti Bonding

Bond order Definition:the difference between the number of bonding electrons and the number of anti bonding electrons divided by two. It is an index of bond strength

Pi molecular orbital Definition:electro n probabilities that lie above and below the line between the nuclei.

Para magnetism Definition:a type of induced magnetism associated with unpaired electrons that causes a substance to be attracted into the inducing magnetic field.

Diamagnetism Definition: a type of magnetism associated with paired electrons that causes a substance to be repelled from the inducing magnetic field.

Hetero nuclear diatomic molecule Definition: different atoms in a diatomic molecule that disables the usage of its energy level diagram.

De-localized Pi Bonding Definition:Of electrons; refers to bonding electrons that are distributed among more than two atoms that are bonded together; occurs in species that exhibit resonance. Benzene structure