UNIT IXLesson #2

Polar Vs Non Polar

Review

BOND TYPE WHAT TO LOOK FOR...

INTRAMOLECULAR BONDS ( within the molecule itself)

IONIC BOND Made up of metal and nonmetal (or recognizable ions)

COVALENT BOND Made up of nonmetal and nonmetal

INTERMOLECULAR BONDS ( between molecules)

HYDROGEN BOND Look for HF or any molecule having OH or NH in its formula

DIPOLE-DIPOLE FORCE Look for an asymmetric molecule

LONDON FORCE Always present

LOOKING AT STRUCTURES TO DETERMINE POLARITY

Other than having permanent dipoles, if we look at the structure of the molecules we can determine if they will be polar molecules, or non-polar molecules.

Molecular Polarity

Polar (H2O)

Molecular Polarity

Non-PolarBF3 Boron Trifluoride

Polar Vs Non-Polar

Which of the following are expected to be polar and which are expected to be nonpolar??

Methane (CH4) Hydrogen Fluoride (HF)

Polar Vs Non-Polar

nonpolar = symmetrical polar = asymmetrical

(if one end of the molecule differs from the other)

Methane Hydrogen fluoride

MORE EXAMPLES…

Borane (BH3) BeF2

CH3Cl SF2

SHAPES OF MOLECULES

C2H6 C3H8

Hydrocarbons are always non-polarHydrocarbons are compounds that contain only carbon and hydrogen.

METHANOL CH3OH AND ETHANOL CH3CH2OH

FYI: FOR YOUR INFORMATION!

Methanol has a high toxicity in humans. If as little as 10 mL of pure methanol is ingested, it can break down into formic acid, CH2O2 which can cause permanent blindness by destruction of the optic nerve!

Ethanol  (Ethyl alcohol)

It is the main type of alcohol found in alcoholic drinks. Ethanol is used as a solvent, an antiseptic, a fuel, in modern thermometers.

HOMEWORK

PAGE 201

QUESTION 10

AND YES, THAT’S IT!