__________________________________Physical States are Energy Dependent

__________________________________ Solids Liquids Gases The Three Common States

__________________________________Physical Changes w/o Identity Loss

__________________________________Terminology of Physical Changes

Changes in State l Freezing and Melting – Freezing /Melting Point: temperature a liquid and solid are at equilibrium at 1 atm – Molar heat of Fusion The amount of energy needed to melt one mole of a solid at its freezing point

Changes in State l Sublimation and Deposition – Sublimation: the change in state from a solid to a gas – Deposition: the change in state from a gas to a solid

Changes in State l Boiling – Boiling: conversion of a liquid to a vapor within the liquid and at the surface – Boiling Point: temperature the equilibrium vapor pressure equals the atmospheric pressure – Energy and Boiling – Molar Heat of Vaporization The amount of energy needed to vaporize one mole of a liquid at its boiling point

Changes in State l Boiling – Boiling: conversion of a liquid to a vapor within the liquid and at the surface

_______________________ 1. Evaporation: the phase change of a non-boiling liquid to a gas 2. Vaporization: the change from a liquid or a solid to a gas 3. Sublimation: the phase change from a solid to a gas Evaporation vs Vaporization

Changes in State l Phase Diagrams: a graph of pressure vs temperature showing conditions for each phase

Changes in State l Phase Diagrams: allow determination of phase changes for various conditions

Changes in State l Phase Diagrams: a graph of pressure vs temperature showing conditions for each phase – Triple Point: the point at which all three phases can exist in equilibrium – Critical Point: The point where critical temperature and pressure overlap Critical Temperature: the maximum temperature for a substance to exist as a liquid Critical Pressure: the minimum pressure for a substance to exist as a liquid

Changes in State l Phase Diagrams: phase changes require gaining or loosing energy

_________________________ _________ Physical Changes & K.E.

Gas Kinetic Molecular Theory Assumptions of the KMT: 1. Particles are unconnected and very far apart 2. Particle Collisions are Elastic without loss of Kinetic Energy 3. Particles motion is continuous, translational, rapid and random 4. Particle attractions or repulsion are negligible 5. Temperature depends on Average Kinetic Energy (KE=½MV 2 )

Gas Kinetic Molecular Theory The Nature of Gases: l Expansion: no definite shape or volume l Fluidity: Negligible attractive forces allow particles to glide past one another l Low Density: High KE and low Attractive forces create large spaces and low density l Compressibility: due to large particle spacing they can be compressed significantly l Diffusion and Effusion

______________________________________ Assumptions of the KMT: 1. Particles are connected loosely 2. Particle Collisions are Elastic without loss of Kinetic Energy 3. Particles motion is continuous, translational, connected and random 4. Particle attractions or repulsion are significant and rarely overcome 5. Temperature depends on Average Kinetic Energy (KE=½MV 2 ) Liquid Kinetic Molecular Theory

__________________________________ 1. Fluidity w/ definite volume not shape 2. High Density w/ average spacing 3. Incompressibility w/ low volume reduction 4. Diffusion w/ random mixing based on particle size 5. Weak intramolecular attractions a. Cohesion: Surface Tension within the liquid b. Adhesion: Between different molecules a.Capillary Action w/ between liquids and solids at surface b.Suspensions w/ between liquids and solids within the liquid Liquid Kinetic Molecular Theory

__________________________________ Assumptions of the KMT: 1. Particles are connected rigidly 2. Particle Collisions do not occur (nonexistent) 3. Particles motion is rotational or vibrational not directional 4. Particle attractions or repulsion are strong and not overcome 5. Temperature depends on Average Kinetic Energy (KE=½MV 2 ) Solid Kinetic Molecular Theory

l Properties of Solids and the KMT – High Density and Incompressibility – No Diffusion – Crystalline or Amorphous Structures – Definite Melting Point Melting: physical change from a solid to a liquid Meting Point: the temperature at which a solid becomes a liquid Super-cooled liquid: substances that retain certain liquid properties in a solid state

Gas Kinetic Molecular Theory Assumptions of the KMT: 1. Particles are unconnected and very far apart 2. Particle Collisions are Elastic without loss of Kinetic Energy 3. Particles motion is continuous, translational, rapid and random 4. Particle attractions or repulsion are negligible 5. Temperature depends on Average Kinetic Energy (KE=½MV 2 )

Gas Kinetic Molecular Theory The Nature of Gases: l Expansion: no definite shape or volume l Fluidity: Negligible attractive forces allow particles to glide past one another l Low Density: High KE and low Attractive forces create large spaces and low density l Compressibility: due to large particle spacing they can be compressed significantly l Diffusion and Effusion

_______________________ 1. Ideal Gases follow the Kinetic Molecular Model 2. At lower temperatures and higher pressures particles attractive forces become more significant and behavior is less ideal and more real or fluid like 3. Real Gases do not follow the Kinetic Molecular Model Ideal vs Real Gases

Gas Kinetic Molecular Theory The Nature of Gases: l Effusion and Diffusion – Effusion: Selective process of passing through a tiny opening – Diffusion: Spontaneous process of mixing of particles due to random motion

__________________________________ Gases are Fastest Liquids are Slower Diffusion rates are dependent on K.E.

______________________________________ Assumptions of the KMT: 1. Particles are connected loosely 2. Particle Collisions are Elastic without loss of Kinetic Energy 3. Particles motion is continuous, translational, connected and random 4. Particle attractions or repulsion are significant and rarely overcome 5. Temperature depends on Average Kinetic Energy (KE=½MV 2 ) Liquid Kinetic Molecular Theory

__________________________________ 1. Fluidity w/ definite volume not shape 2. High Density w/ average spacing 3. Incompressibility w/ low volume reduction 4. Diffusion w/ random mixing based on particle size 5. Weak intramolecular attractions a. Cohesion: Surface Tension within the liquid b. Adhesion: Between different molecules a.Capillary Action w/ between liquids and solids at surface b.Suspensions w/ between liquids and solids within the liquid Liquid Kinetic Molecular Theory

_______________________ 1. Cohesion is the attraction of similar particles to one another 2. Cohesive forces create Surface Tension which causes beading and keeps particles from passing through this barrier Intramolecular Cohesion

_______________________ 1. Adhesion is the attraction between two dissimilar particles. 2. If adhesive forces are stronger the a meniscus is formed like water and glass on the far right 3. If cohesive forces are stronger then beading is formed like mercury and glass on the left Intramolecular Adhesion

________________ l Capillary Action: When Adhesion is stronger than cohesion causing liquid in a capillary tube, of hair-like thickness, or absorbent material to rise or fall as a result of surface tension. Capillary Action

_______________________ 1. Internally Adhesion allows particles to become dissolved like salt in water 2. The Solvent has greater concentration 3. The Solute(s) have less concentration Intramolecular Adhesion

__________________________________ Assumptions of the KMT: 1. Particles are connected rigidly 2. Particle Collisions do not occur (nonexistent) 3. Particles motion is rotational or vibrational not directional 4. Particle attractions or repulsion are strong and not overcome 5. Temperature depends on Average Kinetic Energy (KE=½MV 2 ) Solid Kinetic Molecular Theory

__________________________________ 1. High Density w/ low spacing 2. Incompressibility w/o volume reduction 3. No Diffusion 4. Rigidity w/ definite volume and shape 5. Strong intramolecular attractions a. Amorphous w/ random arrangement b. Crystalline w/ definite lattice patterns Allotropes w/ same material and different patterns Solid Kinetic Molecular Theory

Solids l Properties of Solids and the KMT – Molecular Arrangement – Definite Shape and Volume – Definite Melting Point

Solids l Properties of Solids and the KMT – Molecular Arrangement Crystalline Solids: Solids composed of crystals –Crystals: particles composed of orderly geometrically repeating patterns Amorphous Solids: –Amorphous: particles composed randomly in a disorderly manner

Solids l Properties of Solids and the KMT – High Density and Incompressibility – Low Rate of Diffusion – Definite Melting Point Melting: physical change from a solid to a liquid Meting Point: the temperature at which a solid becomes a liquid Super-cooled liquid: substances that retain certain liquid properties in a solid state

________________________Physical Changes & K.E. Specific Heats of H 2 O are: A.Ice = KJ/Mole˚C B.Ice→Water = 6.009KJ/Mole C.Water = KJ/Mole˚C D.Water→Vapor = 40.79KJ/Mole E.Vapor = KJ/Mole˚C

Solids l Crystalline Solids – Crystalline Structure: The total three- dimensional particle arrangement of a crystal – Binding Forces in Crystals l Amorphous Solids – Lacking a definite repeating pattern – (non-crystals)

Solids l Crystalline Solids – Crystalline Structure: The total three-dimensional particle arrangement of a crystal Unit Cell: The smallest portion of a crystal lattice that shows the entire pattern

Solids l Crystalline Solids Basic Cubic Units: – Simple – Face Centered – Body Centered

Crystalline Solids Cubic Units l Simple – (8 corners) x (1/8 atom) = 1 atom/cube l Face Centered – (8 corners) x (1/8 atom) + (6 faces) (½ atom) = 4 atom/cube l Body Centered – (8 corners) x (1/8 atom) + 1 center atom = 2 atom/cube

__________________________________ 1. Amorphous Solids a. Random arrangements b. Negligible intramolecular interactions c. Low strength and melting points Solid Phases: Carbon with random molecular arrangement and no intramolecular bonding forms coal or soot

__________________________________ 1. Crystalline Solids a. Patterned arrangements b. Intramolecular interactions c. High strength and melting points Solid Phases: Carbon crystals can form Diamonds or Graphite

Solids l Crystalline Solids – Binding Forces in Crystals Ionic Crystals Covalent Network Crystals Metallic Crystals Covalent Molecular Crystals

__________________________________ 1. Ionic Crystals a. Pattern of alternating ions b. Strong intramolecular interactions c. High strength: hard and brittle d. High melting points e. Good insulators Solid Crystal Types

__________________________________ 1. Covalent Network Crystals a. Pattern of connected covalent bonds b. Very strong intermolecular interactions c. High strength: very hard and brittle d. High melting points e. Nonconductors or semiconductors Solid Crystal Types

__________________________________ 1. Metallic Crystals a. Pattern of atoms in a sea of electrons b. Very strong intermolecular interactions c. Variable strength: strong and malleable d. Variable melting points are usually high e. Good conductors Solid Crystal Types

__________________________________ 1. Covalent Molecular Crystals a. Pattern of covalently bonded molecules held together with intramolecular interactions b. Variable intermolecular interactions a.Polar Covalent Dipole-Dipole forces are moderate b.Nonpolar Covalent London Dispersion forces are weak c. Usually low strength and melting points d. Good insulators Solid Crystal Types

Solids l Properties of Solids and the KMT – Definite Melting Point

__________________________________ 1. Different Lattice structures or patterns have different properties a. Allotropes are composed of the same material using different patterns or lattice structures dependent on the intramolecular bonding These bonds can drastically influence properties Solid Crystals:

__________________________________ By changing conditions of formations different crystalline structures are made Carbon Allotropes Diamond & Graphite

__________________________________Carbon Allotropes: Diamond Graphite Ionsdaleite Buckminsterfullerene C540 Fullerite C70 Amorphous Carbon Single Walled Nanotube

__________________________________Carbon Allotropes w/o Identity Loss

__________________________________Changes alter Interactions

__________________________________ 1. The Vapor Pressure of a Gas and a Liquid at a given Temperature 2. Volatile Liquids evaporate easily due to weak attractions between particles 3. Nonvolatile Liquids do not evaporate easily due to stronger attractions between particles Equilibrium Vapor Pressure:

__________________________________Changes occur at an Atomic level

__________________________________ 1. Solubility is the amount of a substance that forms a saturated solution in a solvent at a fixed Temperature 2. Miscible substances mix in all proportions to form Homogenous solutions 3. Immiscible substances are not soluble 4. Saturation is the maximum amount of solute that can be dissolved before a precipitate is formed 5. Unsaturated substances have not reached saturation Intramolecular Adhesions influence:

__________________________________ Solutions are homogenous mixtures of two or more substances uniformly dispersed in a single phase Three Types of Solutions Solution Colloid Suspension

__________________________________ Properties of Solutions, Colloids, Suspension Solution Colloid Suspension

__________________________________ Classes of Colloids Class Phase Example

Changes in State l Equilibrium: a dynamic condition which changes occur at equal rates in a closed system – Equilibrium and Changes in State – Equilibrium Equation – La Chatelier’s Principle – Equilibrium and Temperature and/or Concentration

Changes in State l Equilibrium: – Equilibrium and Changes in State Phase: a part of a system that has uniform composition and properties Condensation: the process by which a gas changes to a liquid

Changes in State l Equilibrium: – Equilibrium Equation Using a reversible yielding symbol – La Chatelier’s Principle An equilibrium disturbed by a stress attains a new equilibrium to minimize the stress

Changes in State l La Chatelier’s Principle with Equilibrium and Temperature and/or Concentration – Liquid + Energy ↔ Vapor Increasing Liquid shift Right Decreasing Liquid shift Left Increasing Vapor shift Left Decreasing Vapor shift Right Decreasing Volume shift Left Increasing Volume shift Right Decreasing Temperature shift Left Increasing Temperature shift Right

Changes in State l Equilibrium Vapor Pressure of a Liquid – The pressure of a vapor in equilibrium with its corresponding liquid at a temperature – Equilibrium Vapor Pressure and the Kinetic Molecular Theory – Liquid Volatility Volatile Nonvolatile

Changes in State l Equilibrium Vapor Pressure of a Liquid – Volatile and Nonvolatile Liquids Volatile: Liquids that evaporate easily with little to no energy Nonvolatile: Liquids that require significant energy to precipitate evaporation –Right

__________________________________ 1. The Vapor Pressure of a Gas and a Liquid at a given Temperature 2. Volatile Liquids evaporate easily due to weak attractions between particles 3. Nonvolatile Liquids do not evaporate easily due to stronger attractions between particles Equilibrium Vapor Pressure:

Water l Structure of water – Polar-Covalent Hydrogen and Oxygen bonds – Hydrogen and Oxygen bond angles of 105˚ – Bent Angular Shape – Oxygen molecule hybridization sp 3

Water l Structure of water – Polar-Covalent Hydrogen and Oxygen bonds – Hydrogen and Oxygen bond angles of 105˚ – Bent Angular Shape – Oxygen molecule with sp 3 hybridization

Water l Physical Properties of Water – Solid density is less than the liquid density allowing solids to float on the liquids – Freezing Point at 1 atm: 0˚C Molar Heat of Fusion: KJ/mole – Boiling Point at 1 atm: 100˚C Molar Heat of Vaporization: KJ/mole