Transcript Intermolecular Forces - Gordon State College

Intermolecular Forces
Vapor Pressure and IF
• The stronger the intermolecular forces of the
compound, the higher the boiling point of the
compound because it will take more energy to
break the bonds.
• It therefore follows that the stronger the
intermolecular forces, the less volatile the
compound will be, which means that its vapor
pressure will be low.
Vapor Pressure
• Compounds with high vapor pressure want to
turn to gas or vapor. Compound with low VP
don’t want to convert to vapor easily unless
more energy is added.
• Therefore compounds with LOW VP have High
Boiling Points because their intermolecular forces
are stronger) and compounds with HIGH VP have
LOW Boiling points (because their intermolecular
forces are weaker).
Summary
• Strong Intermolecular forces  High Boiling
Points  compounds have LOW VAPOR
PRESSURE and are LESS VOLATILE (don’t
evaporate easily)
• Weak Intermolecular forces  LOW Boiling
Points  compounds have HIGH VAPOR
PRESSURE and are MORE VOLATILE (evaporate
easily)