Chemical Bonding-Focus Ionic!

Bonding: Ionic, Metallic, & Covalent

Vocabulary

Chemical Bond attractive force between atoms or ions that binds

them together as a unit

The type of bond is determined by how the valence electrons are shared among the bonded atoms

The energy required to break a bond = “Bond Energy”

Vocabulary

Ionic Bond Formed when valence electrons are completely

transferred from one atom to another.

Not a “real” bond, is an electrostatic attraction of ions!! Attraction between anions and cations Occurs between metals and nonmetals – large

difference in electronegativity.

Valence Electrons:

ELECTRONS AVAILABLE

FOR BONDING

The Formation of Sodium Chloride

Sodium has 1 valence electron

Cl: 1s22s22p63s23p5

Na: 1s22s22p63s1

Chlorine has 7 valence electrons

An electron transferred gives each an octet

The Formation of Sodium Chloride

Cl- 1s22s22p63s23p6

Na+ 1s22s22p6

This transfer forms ions, each with an octet:

IONIC

Bond Formation

Type of Structure

Solubility in Water

Electrical Conductivity

OtherProperties

e- are transferred from metal to nonmetal

high

yes (solution or liquid)

yes

MeltingPoint

crystal lattice

Properties of Ionic Compounds

Physical State

solid

Ionic Bonding - Crystal Lattice

All salts are ionic compounds and form crystals

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Dot Notations – Period 2Lewis dot notations for the valence electrons of the elements of Period 2.

lithium

Liberyllium

Beboron

Bcarbon

C

nitrogen

Noxygen

Ofluorine

Fneon

Ne

Lewis Structures

Electron Dot Diagrams show valence e- as dots distribute dots like arrows

in an orbital diagram 4 sides = 1 s-orbital, 3 p-orbitals EX: oxygen

2s 2pO

X

Lewis Structures

Octet Rule Most atoms form bonds in order to obtain 8

valence e-

Full energy level stability ~ Noble Gases

Ne

Lewis Structures & Bonding Ionic – show transfer of e-

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Ionic Boding!

Lewis Structures & Bonding Examples:

Al & Br

K & O

Lewis Structures & Bonding

Mg & N