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Monday  April 15, 2024    Day 60 Valence Bond Theory Part 2
Textbook Readings : 10.7: Valence Bond Theory:           Hybridization of Atomic Orbitals	Course Lecture 10.9    pdf  Video  Valence Bond Theory 2 10.10  pdf  Video  Valence Bond Theory 3
Hybridization sp3 in methane molecule	sp3d Hybridization and the Trigonal Bipyramidal Arrangement
Objectives 1. Determine molecular hybridization for advanced sp3, sp3d and sp3d2 molecules that may also    contain lone pair electrons.     2.  Determined promoted states and hybrid states for the molecules specified above. 3.  Draw molecular pictures that include  orbital overlap, sigma bond identifications      and bond angles accounting for lone pair distortion of the molecular framework.
Homework Problems For the each of the molecules in 65.1 and 65.2 determine the following:                 i.    Lewis structure                 ii.   Hybridization                 iii.  Electronic and molecular geometry names                 iv.  Ground state of the centermost atom                 v.  Promoted state of the centermost atom                 vi.   Hybrid state of the centermost atom                 vii.  Molecular picture including sigma bonds and lone pair electrons                 viii. Bond angles including distortions due to lone pair influences. 65.1   a.  CH4       b.  NH3      c.  H2O 65.2   a.  AsF5       b.  SF4      c.  BrF3       Click and drag the region below for correct answers 65.1   a.  CH4       b.  NH3      c.  H2O    ...on your own.  Don't "Google it." 65.2   a.  AsF5      b.  SF4        c.  BrF3   ...on your own.  Don't "Google it."

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Tuesday April 16, 2024    Day 61 Valence Bond Theory Part 3
Textbook Readings 10.7: Valence Bond Theory:           Hybridization of Atomic Orbitals	Course Lectures 10.9    pdf  Video  Valence Bond Theory 2 10.10  pdf  Video  Valence Bond Theory 3
Objectives 1. Determine molecular hybridization for     advanced sp3, sp3d and sp3d2 molecules     that may also contain lone pair electrons.     2.  Determined promoted states and hybrid      states for the molecules specified above. 3.  Identify un-hybridized unpaired electrons      and use them to construct off-axis pi bonds.	Sigma and Pi Bonding in Ethene (C2H4) (Hybridization)
Homework Problems         For the each of the molecules in 66.1  determine the following:                 i.    Lewis structure                 ii.   Hybridization                 iii.  Electronic and molecular geometry names                 iv.  Ground state of the centermost atom                 v.  Promoted state of the centermost atom                 vi.   Hybrid state of the centermost atom                 vii.  Molecular picture including sigma bonds and lone pair electrons                 viii. Bond angles including distortions due to lone pair influences.   66.1      a. I3-                      b.   CH3CH3                         c.  CH2CH2          d.   CH2O   Click and drag the region below for correct answers  66.1     a. I3-                         b.   CH3CH3                      c.  CH2CH2              d.   CH2O        (On your own!)

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Wednesday April 17, 2024    Day 62 Intermolecular Forces vs. Intramolecular Forces Solids Liquids Gases
Textbook Readings 11.1: Water in Zero Gravity 11.2: Solids, Liquids, and Gases:           A Molecular Comparison	Course Lectures 11.1 pdf  Video    Intermolecular forces                               and phase changes
Water in Space: Imbedded GoPro	The arrangement of particles in solids, liquids and gases
Objectives:  1.  Describe the similarities and differences between the three phases of matter: solid, liquid and gas. 2.  Distinguish between intermolecular and intramolecular forces.
Homework Problems 1.  Use your textbook and the video above to list the chemical and physical characterisitcs      of solids, liquids and gases.  2.  What does it mean to be "compressible?"       Why are gases compressible while solids and liquids are not compressible? 3.  What are intermolecular and intramolecular forces?  Use  H2O molecule(s)        to to provide diagrams illustrating these two types of forces. 4.  Why are the intermolecular forces between gas phase particles weaker than the forces between        solid and liquid particles? 5.  As we know, nature prefers situations of low energy.  For soap and water bubbles,       this means settling on a shape that has the minumum surface area.  What is this shape? 6.  Define each of the following terms that are used to describe properties of liquids.       a. Density                               b. molecular order               c. compressibility           d. thermal expansion            e. diffusion                             f. fluidity 7.   Intermolecular forces can be described as either cohesive or adhesive.        What's the difference between these forces?     Click and drag the region below for correct answers. 1. Refer to text book for answers. 2. The word "compressible" refers to how a material changes volume when external forces are      applied.  A pillow would be considered compressible while a brick would be incompressible. 3.  Intermolecular forces exist between molecules.  Intramolecular forces exist within a molecule.      The covalent bond within a water molecule is an intramolecular force.  The attraction      between the positive end of one water molecule and the negative end of a different water      molecule is an intermolecular force. 4.  Intermolecular forces depend on distance.  If molecules are far apart, the intermolecular      forces are weak.  I'll leave it up to you make sense of how this applies to solids, liquids and      gases. 5.   A sphere! 6.   Refer to text book for answers. 7.  Cohesive intermolecular forces exist between  molecules of the same substance.      Adhesive forces exist between molecules of different substances.

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Thursday  April 18, 2024    Day 63 Intermolecular Forces:  The details.
Textbook Readings 11.3: Intermolecular Forces:          The Forces that Hold Condensed          Phases Together	Course Lecture 11.6  pdf  Video    Intermolecular forces and details.
Intermolecular Forces and Boiling Points	Hydrogen Bonding and Common Mistakes
Objectives 1.  Rank the common intermolecular forces in order of increasing strength. 2.  Describe the similarities and differences between dipole-dipole attractions      and hydrogen bonding. 3.  Describe the process by which Van der Waals (a.k.a. London Dispersion Forces) develop      beween molecules. 4.  Describe how & why boiling point temperatures depend on the strength of      intermolecular forces.  5.  Arrange molecules in order of increasing boiling point temperatures. 6.  Identify hydrogen bonding between molecules. 7.  Explain why ice is less dense than liquid water and why this is environmentally significant.
Homework Problems 1.  Ion-ion and dipole-dipole intermolecular forces are the result of positives attracting negatives.      However, Van der Waals forces are the attractions between non-polar molecules.      How do Van der Waaals forces work?   2.  Rank the following intermolecular forces in order of increasing strength.      dipole - dipole         ion - ion          ion - dipole           hydrogen bonding       Van der Waals 3.  Determine the types of intermolecular forces that most significantly apply      to each of the following:      a.  NH3              b.  Br2                   c.   PH3                 d.  HF                e.  CCl4      f.   H2                 g.  He                    h. CH3OH            i.  CH3CH3       j.   CaCl2 4.  Use what you know about intermolecular forces to pick which of the following would have      the highest boiling point temperature.  Provide an explanation for your choice.       a.  H2S   or H2O              b.  Br2   or    HBr          c.   NaCl   or    KI        d.  CH3CH2CH2CH3   or    CH3CH3                     e.  CI4    or CF4 5.   Why is ice less dense than liquid water?  Draw a pictures of liquid and solid water that        demonstrates this idea using six water molecules for each of the two figures. Click and drag the region below for correct answers 1.   Van der Waals forces develop when electrons in one molecule, momentarily shift to       one side making it negative and leaving the other side positive.  In response to this,       neighboring molecules also develop momentary positive and negative sides that are       (briefly) attracted to the other molecules around it. 2.    Strongest:  ion-ion                                  ion - dipole                                       hydrogen bonding                                             dipole-dipole                                                       Van der Waals   ...weakest 3. a. Hydrogen bonding        b.  Van der Waals     c.   dipole-dipole    d. Hydrogen Bonding     e. Van der Waals               f. Van der Waals       g. Van der Waals      h. Hydrogen Bonding     i. Van der Waals                j. Ion-ion                 ****Note that Van der Waals attraction is ALWAYS present  ****        The above answers refer  to the most important attraction of all those possible. 4.   a. H2O        b.   HBr        c.   NaCl        d.   CH3CH2CH2CH3       e. CI4  5.   When ice forms from liquid water, hydrogen bonding sets up a structure that contains       more empty space than what was true for water.  More internal empty space (more volume)       decreases the density of the ice.

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