Intermolecular Forces, Ch. 10

condensed state examples
solids and liquids
intermolecuar forces
forces that cause the aggregation of the components of a substance to form a liquid or a solid. (Does not include covalent or ionic bonding)
dipole-dipole attention
molecules with dipole moments can attract each other electrostatically by lining up so the positive and negative ends are close to each other
hydrogen bonding
dipole-dipole attractions between H and N, O, or F
because H is so small, they can get close and N, O, F are highly electronegative
London dispersion forces (LDF)
Forces between noble gases and nonpolar molecules because of an instantaneous dipole moment. Significant for big molecules.
instantaneous dipole
electrons move around and the nonsymmetrical electron distribution can affect the electron distribution of a close atom.
more O–H bonds…
higher boiling point
Liquid characteristics
low compressibility, lack of rigidity, high density,
Why liquid droplet is a sphere?
Less surface area (SA)
Surface tension
Resistance of a liquid to an increase in its surface area
Capillary Action
spontaneous rising of a POLAR liquid in a narrow tube
cohesive forces
Forces between molecules of the liquid. Surface tension and capillary action.
adhesive forces
forces between liquid molecules and their container
why water creeps up sides of glass tube?
because its adhesive forces are stronger than its cohesive forces, forming a concave shape of the meniscus
what raises boiling points?
H bonds, ionic forces, LDF (larger molecule has more), dipole-dipole forces.

Basically, all the forces

the forces that occur between two polar molecules
the force between a noble gas and a nonpolar molecule
London Dispersion Forces (LDF)
bonding between N, O, or F and H
hydrogen bonding
network solids
atoms, molecules, or ions occupy the lattice positions
molecular solids
molecules occupy the lattice points
ionic solids
ions occupy the lattice points
atomic solids
atoms occupy the lattice points