Chemical bonding

Bonding Chemical bond – the transfer or sharing of electrons

Ionic bond- the transfer of electrons Covalent bonding – the sharing of electrons (2)

Nonpolar –nearly equal, or equal sharingPolar - unequal sharing

Ionic Bond

Empirical formula

NaCl

Covalent bondnon polar

• Two chlorine atoms

They always share in pairs

Can be single ( 2 electrons)

Double ( 4 electron, 2 pairs)

Or triple ( 6 electrons, 3 pairs)

Polar bondunequal sharing

• +

• One atom has a greater pull and there for a greater share of the electrons. Giving it a slight negative charge, and the other atom a slight positive charge

Large electronegativity Low electronegativity

( - )(+)

• Electronegativity - measure of an atoms attraction for electrons used for bonding

• The difference in electronegativity values determines the type of bond.

• .4-------------1.7

• Non polar polar ionic

Electronegativity values

VSEPR Theory

• Families 1 2 3 4 5 6 7 8

• X X X X X X X X

• 1 linear diatomic, 2 linear triatomic, 3 planar triangle, 4 tetrahedron, 5 pryamidal, 6 bent, 7 linear diatomic

• Demonstrate models

• Polar and nonpolar Molecules• To determine this two factors must be considered.

• What are the bond types? ( electronegativity diff)

• What is the shape of the molecule ? (VSEPR ) Is it symmetrical or not?

• If the bonds are nonpolar , the molecule is nonpolar• If the bonds are polar and the shape is symmetrical the molecule • is nonpolar• If the bonds are polar and the shape is not symmetrical the molecule is

polar

• Bonds between molecules (intermolecular)

• Dipole – dipole

• Hydrogen bonding

• H- O, H – N, H – F, molecules with these combination have

• Hydrogen bonding

What would make things with no charge attract each other?

• Nonpolar molecules use

• Van Der Waal Forces to form

• liquids

• Also called London forces

• Which are momentary

• dipoles

Momentary dipole

Metallic bonding

• + ions swimming in a sea of electrons.