I II III IV

Chemical Bonding

Introduction toBonding

A. VocabularyChemical Bond

attractive force between atoms or ions that binds them together as a unit

bonds form in order to…decrease potential energy (PE)increase stability

A. Vocabulary

CHEMICAL FORMULA

MolecularFormula

FormulaUnit

IONIC COVALENT

CO2NaCl

A. Vocabulary

COMPOUND

TernaryCompound

BinaryCompound

2 elements more than 2elements

NaNO3NaCl

A. Vocabulary

ION

PolyatomicIon

MonatomicIon

1 atom 2 or more atoms

NO3-Na+

C. Johannesson

IONIC COVALENTBond FormationType of Structure

Solubility in WaterElectrical ConductivityOtherProperties

e- are transferred from metal to nonmetal

high

yes (solution or liquid)

yes

e- are shared between two nonmetals

low

no

usually not

MeltingPoint

crystal lattice true molecules

B. Types of Bonds

Physical State solid liquid or gas

odorous

C. Johannesson

“electron sea”

METALLICBond FormationType of Structure

Solubility in WaterElectrical ConductivityOtherProperties

MeltingPoint

B. Types of Bonds

Physical State

e- are delocalized among metal atoms

very high

yes (any form)

no

malleable, ductile, lustrous

solid

C. Bond PolarityMost bonds are

a blend of ionic and covalent characteristics.

Difference in electronegativity determines bond type.

C. Bond PolarityElectronegativity

Attraction an atom has for a shared pair of electrons.

higher e-neg atom -

lower e-neg atom +

C. Bond PolarityElectronegativity Trend (p. 151)

Increases up and to the right.

Nonpolar Covalent Bond e- are shared equally symmetrical e- density usually identical atoms

C. Bond Polarity

+ -

C. Bond PolarityPolar Covalent Bond

e- are shared unequally asymmetrical e- density results in partial charges (dipole)

C. Johannesson

Nonpolar

Polar

Ionic

View Bonding Animations.

C. Bond Polarity

C. Bond Polarity

Examples:Cl2

HCl

NaCl

3.0-3.0=0.0Nonpolar

3.0-2.1=0.9Polar

3.0-0.9=2.1Ionic