Chapter 8: Bonding And Molecular Structure

Front 1

Axial

Back 1

in the trigonal bipyramidal electron-pair geometry, the two positions directly acoss from each other

Front 2

Bent

Back 2

the molecular geometry of a triatomic molecule or ion in which the bond angle is less than 180 degrees

Front 3

bond angle

Back 3

the angle formed between two bond axes.

Front 4

bond axis

Back 4

an imaginary line connecting the nuclei of two bonded atoms

Front 5

bond dissociation enthalpy

Back 5

the enthalpy change for breaking a bond in a molecule with the reactants and products in the gas phase.

Front 6

bond length

Back 6

the distance between the nuclei of two bonded atoms.

Front 7

bond order

Back 7

the number of bonding electron pairs shared by two atoms in a molecule or polyatomic ion.

Front 8

bonding pair

Back 8

a pair of electrons that is shared betweeen two atoms.

Front 9

bonding

Back 9

describes the forces that hold adacent atoms together

Front 10

chemical bond

Back 10

an attractive force between two atoms that causes the atoms to be attached together.

Front 11

coordinate covalent bond

Back 11

a covalent bond in which both electrons in the bond were contributed by one atom.

Front 12

core electrons

Back 12

all of the electrons in atom except for the valence electrons

Front 13

covalent bond

Back 13

a force of attraction between two atoms that results from the sharing of electrons in the valence shells of two atoms

Front 14

dipole moment

Back 14

the product of the magnitude of the partial charges on a molecule and the distnace by which they are separated. The dipole moment is a vector quantity having both a magnitude and a direction

Front 15

double bond

Back 15

a double bond exists when four eletrons are shared by two atoms; two pairs of electrons are shared.

Front 16

eleelectronegativity

Back 16

a measure of the ability of an atom in a molecule to attract electrons to itself

Front 17

electroneutrality principle

Back 17

electrons in a molecule or polyatomic ion will be distributed in such a way that the charges on all atoms are as close to zero as possible

Front 18

Electron-pair geometry

Back 18

the geometry taken up by the valence electron pairs around a central atom

Front 19

equatorial

Back 19

in the trigonal bipyramidal electron-pair geometry, the three politions in a plase midway between the two axial positions

Front 20

Formal Charge

Back 20

Formal Charge = group number - [Lone pair electrons + 1/2 bonding electrons]

Front 21

Free radical

Back 21

a chemcial species containing an unpaired electron; these tend to be very reactive.

Front 22

Ionic Bond

Back 22

the electrostatic attraction between two oppositely charged ions. Ion formation results from the tranfer of electrons from one atom to another

Front 23

Isoelectronic

Back 23

containing the same number and arrangement of electrons

Front 24

Isostructural

Back 24

having the same structure

Front 25

Lewis electron dot symbol

Back 25

in a lewis dot symbol for an atom, the chemical symbol is used to represent the nucleus and core electrons of an atom; the valence electrons are represnted by dots place around the symbol

Front 26

Lewis structure

Back 26

a representation of a covalenty bonded species in which the chemical symbol is used to represent the nucleus and core electrons of each atoms; a lone pair belonging solely to one atom is represented by two dots. and a pair of electrons that is shared between two atoms is represented by a line connecting two atoms

Front 27

Resonace Structure/ Formal Charges

Back 27

To predict formal charge for a resonace structure. take the sum of the outer atoms/ it by the amount of outer atoms

Front 28

Bond order
For Valence Bond Theory

Back 28

Bond order = Number of shared pairs in all X-Y Bonds/ Number X-Y links in the molecule or ion

Front 29

Bond order
For MO theory

Back 29

Add up full orbitals and half full orbitals fractonal bonding is allowed

Front 30

paramagnetic
MO Theory

Back 30

Unpaired Electron

Front 31

Diamagnetic

Back 31

all electrons are paired

Front 32

HEOMO
Highest energy occupied molecular orbital

Back 32

the hieghts occupied orbital on the diagram

Front 33

sigma bond

Back 33

a sigma bond is a bond in which electrons density is greatest along the axis of the bond

Front 34

pi pond

Back 34

a covalent bond that resluts from the sidways overlap of unhbridized p orbital on two different atoms. a pi bond concentrates electron density above and below the bond axis