Advanced Theories of Covalent Bonding

Question 1

Valence Bond Theory

Answer 1

Description of bonding that involves atomic orbitals overlapping to form sigma or pi bonds, within which pairs of electrons are shared

Question 2

Overlap

Answer 2

Coexistence of orbitals from two different atoms sharing the same region of space, leading to the formation of a covalent bond

Question 3

Sigma Bonds

Answer 3

Covalent bond formed by overlap of atomic orbitals along the internuclear axis

Question 4

Pi Bonds

Answer 4

Covalent bond formed by side-by-side overlap of atomic orbitals; the electron density is found on opposite sides of the internuclear axis

Question 5

Node

Answer 5

Plane separating different lobes of orbitals, where the probability of finding an electron is zero

Question 6

Hybridization

Answer 6

Model that describes the changes in the atomic orbitals of an atom when it forms a covalent compound

Question 7

Hybrid Orbitals

Answer 7

Orbital created by combining atomic orbitals on a central atom

Question 8

sp Hybrid Orbitals

Answer 8

One of a set of two orbitals with a linear arrangement that results from combining one s and one p orbital

Question 9

sp^2 Hybrid Orbitals

Answer 9

One of a set of three orbitals with a trigonal planar arrangement that result from combining one s and two p orbitals

Question 10

sp^3 Hybrid Orbitals

Answer 10

One of a set of four orbitals with a tetrahedral arrangement that results from combining one s and three p orbitals

Question 11

sp^3d Hybrid Orbitals

Answer 11

One of a set of five orbitals with a trigonal bipyramidal arrangement that results from combining one s, three p, and one d orbital

Question 12

sp^3d^2 Hybrid Orbitals

Answer 12

One of a set of six orbitals with an octahedral arrangement that results from combining one s, three p, and two d orbitals

Question 13

Paramagnetism

Answer 13

Phenomenon in which a material is not magnetic itself but is attracted to a magnetic field; it occurs when there are unpaired electrons present

Question 14

Diamagnetic

Answer 14

Phenomenon in which a material is not magnetic itself but is repelled by a magnetic field; it occurs when there are only paired electrons present

Question 15

Molecular Orbital Theory

Answer 15

Model that describes the behavior of electrons delocalized throughout a molecule in terms of the combination of atomic wave functions

Question 16

Molecular Orbital

Answer 16

Region of space in which an electron has a high probability of being found in a molecule

Question 17

Homonuclear Diatomic Molecules

Answer 17

Molecule consisting of two identical atoms

Question 18

Linear Combination of Atomic Orbitals (LCAO)

Answer 18

Technique for combining atomic orbitals to create molecular orbitals

Question 19

Sigma-s Bonding Orbital

Answer 19

Molecular orbital in which the electron density is found along the axis of the bond

Question 20

Sigma-s-star Bonding Orbital

Answer 20

Antibonding molecular orbital fomed by out-of-phase overlap of atomic orbital along the axis of the bond, generating a node between the nuclei

Question 21

Bonding Orbitals

Answer 21

Molecular orbital located between two nuclei; electrons in a bonding orbital stabilize a molecule

Question 22

Antibonding Orbitals

Answer 22

Molecular orbital located outside of the region between two nuclei; electrons in an antibonding orbital destabilize the molecule

Question 23

Pi Bonding Orbital

Answer 23

Molecular orbital formed by side-by-side overlap of atomic orbitals, in which the electron density is found on opposite sides of the internuclear axis

Question 24

Pi-star Bonding Orbital

Answer 24

Antibonding molecular orbital formed by out of phase side-by-side overlap of atomic orbitals, in which the electron density is found on both sides of the internuclear axis, and there is a node between the nuclei

Question 25

Degenerate Orbitals

Answer 25

Orbitals that have the same energy

Question 26

Molecular Orbital Diagram

Answer 26

Visual representation of the relative energy levels of molecular orbitals

Question 27

Bond Order

Answer 27

Number of pairs of electrons between two atoms; it can be found by the number of bonds in a Lewis structure or by the difference between the number of bonding and antibonding electrons divided by two

Question 28

s-p Mixing

Answer 28

Change that causes sigma-p orbitals to be less stable than pi-p orbitals due to the mixing of s and p-based molecular orbitals of similar energies