Intermolecular Forces Flashcards
Three types of intermolecular forces
Dipole dipole force, hydrogen bond, dispersion force
Dipole dipole force
And intermolecular force, the attraction of a positive end of one polar molecule to the negative end of another polar molecule
Hydrogen bond
A special dipole dipole forces involved in hydrogen and a highly electronegative element (fluorine, oxygen, or nitrogen)
What is the strongest intermolecular force
Hydrogen bond
Dispersion force
An electrostatic attraction that arises between Adams or molecules because of the presence of instantaneous and induce temporary dipoles
Kinetic molecular theory for solids(5)
Always moving in vibrating, high density, little diffusion, expand when increased temperature, do not compress
Two types of solids
Crystalline and amorphous
Crystalline solid
I solid in which the particles of her in a regular repeating pattern
Amorphous solid
A solid in which the particles occur in random positions with no orderly pattern, shape, or form or structure
Crystalline substances
Have exact melting points because all the bonds are the same
Amorphous substances
Gradually soften as they are heated
Sublimation
A physical change from the solid directly to the gaseous state
Desposition
Physical change from the gas directly to the solid
Crystal lattice
I repeating three-dimensional pattern of positive and negative ions in a crystal
Unit cell
The simplest unit of repetition in a crystal lattice, “building block”
Polymorphous
Describes a substance (either an element or compound) that occurs in more than one crystalline form
Allotropic
Describes an element that has more than one crystalline form
types of crystalline solids(5)
Atomic, covalent molecular, covalent network, ionic crystals, metallic crystals
Atomic
Frozen noble gases
Covalent molecular
How together by hydrogen bonds, dipole, and dispersion forces
Covalent network
Like giant molecules
Ionic crystals
Repeating crystal lattice pattern
Metallic crystals
Metallic bonding
Kinetic description of liquids(4)
Touching, not locked in place, little expansion or compression, permeability
Two affects of intermolecular attractions
Cohesion and adhesion
Cohesion
Attraction between particles
Adhesion
Attraction between particles and other substances
Surface tension
The tightening of a surface of a liquid due to unbalanced intermolecular forces on the surface particles
Surfactant
A substance which reduces the surface tension
Viscosity(3)
The thickness of a liquid, the ability of a liquid to resist flow, decreases as temperature rises
Meniscus
The curved upper surface of a column of liquid
Capillary action
The movement of a liquid up a narrow tube caused by the attraction of the molecules of a glass tube to the molecules of a liquid
Diffusibility
Drop of food coloring diffuses through out a glass of water
Permeability
Spilled milk permeates through a paper towel
Wetness
A liquid “wets” a surface if the attraction of the liquid to the surface is greater than the attraction of the liquid to itself
Intermolecular forces
And electrostatic attraction between molecules; it is much weaker than the bonds that form within molecules
Lattice energy
The energy released when gaseous particles form a crystal
Vaporization
A physical change from a liquid to a vapor or gaseous state
Evaporation
A physical change from liquid to gas that occurs at the surface of a liquid
Vapor pressure
Due to evaporated molecules above a liquid
Boiling
Rapid change from liquid to gas
Boiling point
Temperature at which the vapor pressure equals the applied pressure
Normal boiling point
The temperature at which the vapor pressure equals 760torr
Distillation
The process of separating a mixture by boiling one substance, condensing it, and collecting the liquid
Phase diagram
Shows pressure and temperature at which a substance is a solid, liquid, or gas
Triple point
The pressure and temperature at which a substance coexists as a solid, liquid, and gas
Critical temperature
The highest temperature at which a gas can be liquefied
Critical pressure
The pressure that is required to liquefy a gas at its critical temperature
