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Gas --> Liquid
Condensation
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Liquid --> Solid
Freezing
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Liquid --> Gas
Evaporation or Boiling
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Solid --> Gas
Sublimation; I.E. Dry ice
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Gas --> Solid
Deposition (Depositing gas into solid)
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Types of intermolecular forces.
ION-DIPOLE- Between ion and dipole covalent bond
DIPOLE-DIPOLE- Between 2 polar bonds
INDUCED DIPOLE/INDUCED DIPOLE- Temporary, (London/ Van der Waal)
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Ion-Dipole Bonding:
Oxygen is the most electronegative; the addition of both forces, equal but opposites.
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Induced Dipole/Induced Dipole:
(Temporary)- They are weaker forces
- Equal but as it approaches the atoms move away from eachother
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Hydrogen Bonding: (Dipole-Dipole interactions with Hydrogen)
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Dispersion forces:
Larger, heavier molecules have larger dispersion forces than smaller lighter ones. Large can induce a dipole more easily.
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As polarity ____, boiling point will ______.
Increase/Increase
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As molecular weight ______, Boiling point will _____.
Increase/Increase
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Vapor pressure _____ with temperature.
Increases
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The ______ the molecular forces, Vapor pressure will _____.
Weaker/Increase
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When vapor is at 1 atm, its is said to be
Normal Boiling Point
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When a solid is at 0 --> liquid at 0
- Melting; I.E. Ice-->water
- * no temperature change bc it overcomes intermolecular forces.
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Phase Diagram:
 - TRIPLE POINT: s, l, g coexist all at the same time
- CRITICAL POINT: Phase above liquid, SUPERCRITICAL FLUID- Density like gas and solvent properties like liquid
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Cohesive forces
- Intermolecular forces holding substance together; They pull.
- In the case of Hg in a glass the cohesive forces are stronger than adhesive forces causing a miniscus.
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Adhesive forces:
- Attractive forces between substance and surface.
- In the case of Water in a glass, Adhesion is stronger than cohesive and therefore forms a miniscus which takes the shape of the cylindar is is in.
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Difference between Cohesive and Adhesive forces
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Gas molecules are in constant random motion. These gas molecules possess high kinetic energy. This high KE overcomes the attractive forces between molecules and keeps the molecules far apart.
Kinetic Molecular Theory
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Still move and will take the shape of the container
Liquid
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Definite shape and volume. Molecules have motion
Solid
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When rate of gas>liquid is equal to rate of liquid>gas, equilibrium has been established. The number of molecules in the gas phase and the number of molecules in the liquid phase do not change. As quickly as some condense, some others evaporate. The process is
Dynamic
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As the temperature of a liquid is increased, the average kinetic energy of the molecules increases and the vapor pressure increases.
Boiling
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Temperature and pressure above which the liquid and vapor are indistinguishable
Critical temperature and pressure
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Add heat (increase temperature). When you reach the melting point, all heat is used to overcome intermolecular forces and convert solid to liquid. Once the entire compound is a liquid, then heat added is used to raise temperature.
Melting
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measure of resistance to flow
Viscosity
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force that causes the surface of liquid to contract to a minimum. It acts like a membrane
Surface tension
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liquid “creeps” up side of tube due to adhesive forces between liquid and surface
Capillary Action
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2 types of solids:
- Crystalline solids – homogeneous solid in which atoms, ions, or molecules are arranged in a definite repeating pattern
- Amorphous solids – solid where molecules are arranged in random order (usually large molecule)
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How many atoms are contained per unit cell
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1) A point or atom lying completely within a unit cell belongs to that unit cell and counts as one
- 2) An atom lying on a face or a unit cell is shared by 2 unit cells and counts as one-half
- 3) An atom on an edge is shared by 4 unit cells and counts as one-quarter
- 4) An atom at a corner is shared by 8 unit cells and counts as one-eighth
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