(Prelim) States of Matter Flashcards
Manifestations of Intermolecular forces:
- Repulsive and Attractive forces
- Adhesion –attraction of unlike molecules
- Cohesion –attraction of like molecules
attraction of like molecules
Cohesion
attraction of unlike molecules
Adhesion
necessary in order that molecules cohere/adhere
Attractive forces
necessary in order that the molecules do not
interpenetrate one another.
Repulsive forces
due to the interpenetration of the electronic clouds of molecules and increases exponentially with a decrease in distance between the molecules.
Repulsion
At certain equilibrium distance, about ________________, the repulsive and attractive forces are equal
3 or 4x10-8 cm (3 or 4angstroms)
- Attraction between nonpolar
molecules - Weakest
London Forces
Attractions occur between nonpolar molecules and ions.
Ion-induced dipole forces
Types of Intermolecular Forces
- Van der Waals Forces
- Ion-induced dipole forces
- Ion-Dipole Forces
- Hydrogen Bonding
- Hydrophobic Interactions
- Orientation Effect
- Attraction between polar molecules
- Strongest
Keesom Forces
3 Van der Waals Forces
- Keesom Forces
- Debye Forces
- London Forces
- Induction effect
- Attraction between nonpolar and
polar molecules
Debye Forces
involved in the formation of the iodide
complex
Ion-induced dipole forces
These types of interactions account in
part for the solubility of ionic crystalline substances in water
Ion-induced dipole forces
Attractions occur between polar
molecules and ions.
Ion-Dipole Forces
Because of the small size of hydrogen
atom, it can move in close to the electronegative atom and form an electrostatic type of union known as hydrogen bond or hydrogen bridge.
Hydrogen Bonding
It is a special type of dipole-dipole in which hydrogen is bonded to an electronegative element.
Hydrogen Bonding
Forces of attraction between non
polar atoms and molecules in water.
Hydrophobic Interactions
It can exist as Intramolecular and Intermolecular forces of attraction.
Hydrogen Bonding
liquid to solid
freezing
- Strongest
- Definite
- Definite
- Vibration
Solid
They cause the nonpolar species to
be driven together and are critical for
the structure and stabilization of
many molecules including proteins
(with non-polar amino acids) and
aggregates of amphiphiles.
Hydrophobic Interactions
Phases/States
Solid
Liquid
Gas
- Melting/fusion
- Evaporation
- Condensation
- Freezing
- Sublimation
- Deposition
Physical Changes
- Strong
- Definite
- Indefinite
- Gliding/flowing
Liquid
- Weakest
- Indefinite
- Indefinite
- Constant random motion
Gas
gas to solid
deposition
solid to liquid
melting
solid to gas
sublimation
gas to liquid
condensation
liquid to gas
evaporation
- Higher kinetic energy
- Held together by weak
intermolecular forces. - Have no regular shape.
- Compressible
- Invisible
Characteristics of Gases
7 Gas Laws
- Boyle’s Law
- Charles’s Law
- Gay-Lusaac’s Law
- Combined Gas Law
- Ideal Gas Law
- Avogadro’s Law
- Dalton’s Law of Partial Pressure
states that the pressure and absolute temperature of a given mass of a gas at constant volume are directly proportional
Gay-Lusaac’s Law
relates the volume and pressure of a given mass of gas at constant temperature.
Boyle’s Law
states that the volume and absolute temperature of a given mass of
a gas at constant pressure are directly proportional.
Charles’s Law
the summary of the relationship of the three gas laws presented earlier.
Combined Gas Law
infinite volume = non-attracting molecules
Ideal Gas Law
universal gas constant
0.08205 𝑳𝒂𝒕𝒎/𝒎𝒐𝒍𝑲
𝑉= n
Avogadro’s Law
The total pressure (Pt) is the sum of the individual partial pressure of each component in the system.
Dalton’s Law of Partial Pressure
1 mole =
6.02 x 1023
The theory was developed to explain the behavior of gases and supported the validity of the gas laws
Kinetic Molecular Theory
Gases are composed of particles called molecules, the total volume of which is so small as to be negligible in relation to
the volume of the space in which the molecules are confined
Kinetic Molecular Theory
The particles of the gas do not attract one another but rather move with complete independence
Kinetic Molecular Theory
The particles exhibit continuous random motion owing the kinetic energy. The average kinetic energy is directly proportional to the absolute temperature of the gas.
Kinetic Molecular Theory
composed of particles called molecules
Gases
The molecules exhibit perfect elasticity, that is, there is no net loss of speed after they collide with one another and with the walls of the confining vessel, which latter effect accounts for the gas pressure. Although the net velocity, and therefore the average kinetic energy, does not change in collision, the speed and energy of the individual molecules may differ widely at any instant.
Kinetic Molecular Theory
have low internal pressures and are not able to over come the powerful cohesive forces of the polar solvent molecules.
Nonpolar molecules
type of matter with specific properties that make it less rigid than a solid but more rigid than a gas.
Liquid State
have high internal pressures and serve as solvents only for substances of similar internal pressures
Polar liquids
maximum temperature, above
which a liquid can no longer
exist
Critical Temperature
critical temperature of water:__________;
critical pressure: __________
374°C or 647°K;
218 atm
pressure required to liquefy a gas at its critical temperature, which is also the highest vapor pressure that the liquid can have.
Critical Pressure
