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CH1012
VAN DER WAALS
FORCES
Van der Waals forces
- intermolecular attractive forces
- intermolecular attractive forces
1) Dipole-dipole
forces
polar molecules
e.g. the b.p. of organic cmpds increases with increasing m
dipole moment
e.g. the b.p. of organic cmpds increases with increasing m
dipole moment
2) Hydrogen
bonds polar molecules
typically involves either H-F, H-N or O-H
typically involves either H-F, H-N or O-H
eg. water dissolves so many
substances because of it’s
high H-bonding ability
substances because of it’s
high H-bonding ability
