Chapter 11 - Intermolecular Forces Flashcards
Dipole dipole interactions
If there are polar molecules
More polar= higher boiling point
London dispersion forces
Attractions between instantaneous dipole and induced dipole
-present in all molecules
-van der waals force
-long skinny have stronger
dispersion
Increase with molecular weight
- strength of dispersion forces increases with molecular weight because they have larger e clouds (easier to polarize)
Hydrogen bonding
h is bonds to n, o, or f
Arises from high electro negativity
H nucleus is exposed
Ion dipole
Reason why salt dissolves quickly
Must be ions and polar molecules
Viscosity
Resistance of liquid to flow
- increases with stronger intermolecular forces
- decreases with higher temperature
Heat of sublimation
Heat of fusion+ heat of vaporization
Vapor pressure
At any temp some molecules in a liquid have enough energy to break free
- as they break free pressure increases
State of substance depends on
Kinetic energy of particles
Intermolecular forces
Responsible for boiling and melting point
All electrostatic but weaker than ionic bonds
Surface tension
Rises from intermolecular forces
Results from net inward force experienced by molecules on the surface of liquid
C point on phase diagram
Liquid and vapor are indistinguishable from each other
T point on phase diagram
All the states are in equilibrium
When gases are treated as real
Volume and temp increases
Pressure decreases
Why is ice less dense than water
H bond in ice creates lattice structure with holes
Diamonds have higher melting point
More orderly structure
