Lab Chem Ch. 6 Review

Chemical bond

An attractive force between atoms and/or ions

OCTET rule

Compounds form so that each atom has an octet(8) of valence electrons

Hydrogen octet

Only needs 2

Covalent bond

Nonmetal with nonmetal

Ionic bond

Metal with nonmetal

Metallic bond

Metal with metal

non polar covalent bond

Bonding electrons shared equally between two atoms

Polar covalent bond

Bonding electrons shared unequally between two atoms

Dipole

Like a mini magnet

Dipole arrow

No arrow with ionic or non polar

Lewis Structure

Represents the valence electrons for the atoms in a molecule

What is the central atom?

Carbon is always central

VESPR

Valence Shell Electron Pair Repulsion

VSEPR theory

The ideal arrangement for electron pairs is the one that minimizes the repulsion

Unshared pairs

Are highly repulsive and compress the bond angles

octet rule exceptions

More than 8 (central atom must be in period 3-7 and be bonded to a highly EN atom(F

Resonance

Bonding that is shown with more than one Lewis Structure

What do the properties of substances depend on?

Electron Configurations(# of valence electrons)

Intramolecular

within a molecule

Intermolecular

Between molecules

Which one is weaker?

Intermolecular forces are weaker than intramolecular forces

Covalent bond

To break a ——————— bond costs around 400 kJ/mol

Intermolecular bond

To break an ——————- bond costs about 15kJ/mol

Intermolecular forces

Dipole-dipole forces

Dipole-dipole forces

Dipole occurs when equal but opposite charges are separated by a short distance

Hydrogen bonding

An H atom is a polar bond is attracted to an unshared electron pair in F

LDF

Forces between non-polar molecules or atoms

LDF is stronger....

...for molecules/atoms with an increasing number of electrons

As atoms bond with each other

they...

Bonding in molecules or ions that cannot be correctly represented by a singe Lewis Structure is...

Resonance

A molecule with Polar Bonds can be considered non polar if the polar bonds are arranged symmetrically around the central atom

True