Chapter 10 - Chemical Bonding I: The Lewis Model

Lewis Electron-Dot Structure

a structural formula that represents the element and its valence electrons

Ionic Bond

Formed when one or more electrons are transferred from one atom to another

Covalent Bond

A chemical bond that involves sharing a pair of electrons between atoms in a molecule

Metallic Bonding

the chemical bonding that results from the attraction between metal atoms and the surrounding sea of electrons; a pool of electrons

Lewis Symbol

representation of the valence electrons of main-group elements as dots surrounding the element symbol

Octect

atoms with eight valence electrons; full s and p sublevels; eight dots on the Lewis model

Duet

a Lewis structure with two dots, a filled outer later of valence electrons

Chemical Bond

sharing or transfer of electrons to attain stable electron configurations for the bonding atoms

Octect Rule

bonding atoms attain stable electron configurations; the stable configuration is usually eight electrons in the outermost shell

Lattice Energy

energy associated with the formation of a crystalline lattice of alternating cations and anions from the gaseous ions

Born-Haber Cycle

hypothetical series of steps that represents the formation of an ionic compound from its constituent elements

Bonding Pair

a shared pair of electrons

Lone Pair (Non-Bonding Electrons)

a pair of electrons that is associated with only one atom; not involved in bonding

Double Bond

when two atoms share two pairs of electrons

Triple Bond

shorter and stronger than double bonds

Polar Covalent Bond

intermediate in nature between a pure covalent bond and an ionic bond

Electronegativity

the ability of an atom to attract electrons to itself in a chemical bond; results in polar and ionic bonds

Dipole Movement

occurs any time there is a separation of positive and negative charge

Percent Ionic Character

ratio of a bond's actual dipole movement to the dipole movement it would have if the electron were completely transferred from one atom to the other, multiplied by 100%

Resonance Structure

one of two or more Lewis structures that have the same skeletal formula, but different electron arrangements

Resonance Hybrid

the actual structure of the molecule that is intermediate between two or more resonance structures

Formal Charge

fictitious charge assigned to each atom in a Lewis structure that helps us to distinguish among competing Lewis structures

Free Radicals

molecules and ions with an odd number of electrons in their Lewis structures

Bond Energy

energy required to break 1 mole of the bonds in the gas phase

Bond Length

represents the average length of a bond between two particular atoms in a large number of compounds