Content Category 5B: Nature of molecules and intermolecular interactions

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Covalent bonding involves the sharing of electrons between atoms. If the result of such interactions is not a network solid, then the covalently bonded substance will be discrete and molecular.

The shape of molecules can be predicted based on electrostatic principles and quantum mechanics since only two electrons can occupy the same orbital. Bond polarity (both direction and magnitude) can be predicted based on knowledge of the valence electron structure of the constituent atoms. The strength of intermolecular interactions depends on molecular shape and the polarity of the covalent bonds present. The solubility and other physical properties of molecular substances depend on the strength of intermolecular interactions.

The content in this category covers the nature of molecules and includes covalent bonding, molecular structure, nomenclature, and intermolecular interactions.

Topic	Organic Chemistry with a Biological Emphasis, Vol. 1
Covalent Bond (GC) Lewis Electron Dot formulas Resonance structures Formal charge Lewis acids and bases Partial ionic character Role of electronegativity in determining charge distribution Dipole Moment σ and π bonds Hybrid orbitals: sp³, sp², sp and respective geometries Valence shell electron pair repulsion and the prediction of shapes of molecules (e.g., NH3, H2O, CO2) Structural formulas for molecules involving H, C, N, O, F, S, P, Si, Cl Delocalized electrons and resonance in ions and molecules Multiple bonding Effect on bond length and bond energies Rigidity in molecular structure Stereochemistry of covalently bonded molecules (OC) Isomers Structural isomers Stereoisomers (e.g., diastereomers, enantiomers, cis/trans isomers) Conformational isomers Polarization of light, specific rotation Absolute and relative configuration Conventions for writing R and S forms Conventions for writing E and Z forms	Ch. 1.1-3.9, pp. 5-173
Liquid Phase - Intermolecular Forces (GC) Hydrogen bonding Dipole Interactions Van der Waals’ Forces (London dispersion forces)	Ch. 1.4B-D

Topic

Organic Chemistry with a Biological Emphasis, Vol. 1

Covalent Bond (GC)

Lewis Electron Dot formulas
- Resonance structures
- Formal charge
- Lewis acids and bases
Partial ionic character
- Role of electronegativity in determining charge distribution
- Dipole Moment
σ and π bonds
- Hybrid orbitals: sp³, sp², sp and respective geometries
- Valence shell electron pair repulsion and the prediction of shapes of molecules (e.g., NH3, H2O, CO2)
- Structural formulas for molecules involving H, C, N, O, F, S, P, Si, Cl
- Delocalized electrons and resonance in ions and molecules
Multiple bonding
- Effect on bond length and bond energies
- Rigidity in molecular structure
Stereochemistry of covalently bonded molecules (OC)
- Isomers
  - Structural isomers
  - Stereoisomers (e.g., diastereomers, enantiomers, cis/trans isomers)
  - Conformational isomers
- Polarization of light, specific rotation
- Absolute and relative configuration
  - Conventions for writing R and S forms
  - Conventions for writing E and Z forms

Ch. 1.1-3.9, pp. 5-173

Liquid Phase - Intermolecular Forces (GC)

Hydrogen bonding
Dipole Interactions
Van der Waals’ Forces (London dispersion forces)

Ch. 1.4B-D

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