Covalent Bonding

Atoms are held together by SHARING electrons

Covalent Bond

MoleculeNeutral group of atoms joined together by

covalent bonds

Terms

Compounds

Molecule consisting two of the same atomNever exist by themselves

Example: Oxygen (O2)

Diatomic Molecule

Also Known As:

TheMagnificen

tSeven

Diatomic Molecules

Nitrogen

Oxygen

Flourine

Clorine

Bromine

Iiodine

Molecular CompoundCompound

composed of molecules

Collection of +ve and –ve charged ions repeating in a 3D pattern

CompoundsIonic Compound

Lower melting and boiling points compared to ionic compounds

Composed of two or more non-metals

Molecular Compound

Practice Worksheet: Identifying Ionic versus Molecular Compounds

Writing Formulas for Molecular Compounds

Composed of two elementsMetal and non-metal

Binary Molecular Compounds

Chemical formula of a molecular compoundExample: Water

H2O

Molecular Formula

Represents the ACTUAL number of atoms in each molecule (NOT the lowest ratio)

Example: Ethane C2H6

Molecular Formula

Naming Molecular Compounds

PreFixesNumber Prefix

1 Mono-

2 Di-

3 Tri-

4 Tetra-

5 Penta-

6 Hexa-

7 Hepta-

8 Octa-

9 Nona-

10 Deca-

Rules:The name of a molecular compound indicates:

# of atomstype of elements

Prefix “mono” ONLY used on the second element

For example:CO is carbon monoxide rather than carbon

oxide.

Let’s PracticeSO2

SF6

CCl4

NI3

More Practice…CF4

SiO2

SO3

P4S3

Practice WorksheetNaming Ionic and Covalent Bonds

The Nature of Covalent BondingGrab a WHITEBOARD, MARKER AND TOWEL

Electrons are shared so that each atom:

gets eight electronsOr attains the noble gas

configuration)

The Nature of Covalent Bonding

The atom with the LEAST amount of valence electrons normally is in the middle…

Exception: Hydrogen is ALWAYS on the outside

Example: HOCl

Hint

Sometimes the molecular formula tells you the arrangement of atoms

Example: CH3COOH

Hint

Two atoms held together by sharing ONE PAIR of electrons

Pair of shared e- can be represented by a dashStructural formula

Example: Hydrogen Molecule (H2)

Water (H2O)

Single Covalent Bond

Not shared between atomsAlso known as:

Lone PairNon-Bonding

Example: A fluorine molecule (F2)

Unshared Pair

H2O2

PCl3

Practice

Bromine

Chlorine

Iodine

Practice

Double Covalent BondAtoms share two

pairs of electronsAtoms share three

pairs of electrons

Other Covalent BondsTriple Covalent Bond

O2

N2

Double and Triple Bonds

C2H6O

NH3

Double and Triple Bonds

CO

CF4

Try These…

Coordinate Covalent Bonds

A covalent bond in which one atom contributes BOTH bonding electrons

Example:CO2

Coordinate Covalent Bond

SO3

ClO3

Coordinate Covalent Bonding

NH4

Try this one…

REVIEW: A tightly bound group of covalently bonded

atoms that have a positive or negative charge and behave as a unit

Example: [SO3]2-

Drawing Polyatomic Ions

Contain both covalent and coordinate covalent bonds

Electronegativity:The ability of an atom to attract electrons when

the atom is in a compoundMore electronegative elements will GAIN

electronsLess electronegative elements will LOSE

electrons[OH]-

Polyatomic ions

[BF4]-

[SO4]2-

[CO3]2-

Practice

[BF4]-

Practice Problems

[SO4]2-

Practice Problems

[CO3]2-

Practice Problems

Ionic vs. Covalent Bonding

Bonding Videos…