UNIT 5: Chemical Bonds

• Covalent bond


  sharing of e-.
• Ionic bond


  transferring of e-.
• Nonpolar covalent bond


  equal sharing of e-.
• Polar covalent bond


  non-equal sharing of e-.
• pi


  what is this?

  
• sigma


  what is this?

  
• Octet Rule


  atoms will gain or lose sufficient e- to achieve an outer e- arrangement identical to a noble gas.
• Lewis Dot


  representation of valence e-.
• Bond polarization


  result of shared e- being attracted to the more EN atom.
• Ions


  carries a positive or negative charge
• Cations


  positive ions
• Anions


  negative ions
• electrons in the outermost shell of an atom

  Valence Electrons
• Formal Charge


  use to determine the distribution of electrons in a molecule or ion and to evaluate the stability of different resonance structure.
• Expanded Octet


  occurs when an atom is able to have more than 8 valence electrons
• Incomplete Octet


  The number of electrons surrounding the central atom in a stable molecule is fewer than eight.
• Odd-Electron Molecules


  molecules whose total number of valence electrons is an odd number
• Oxidation Numbers


  # of e- an atom can donate or accept to form a bond with another atom.
• Valence Shell Electron Pair Repulsion


  Based on the repulsion of electron pairs, three-dimensional shapes of molecules can be predicted. 
• Molecular Geometry


  focuses only on the arrangement of atoms in the molecule
• Electron Domain


  three-dimensional arrangement of all electron domains around the central atom in a molecule or ion
• Dipole Moment


  measure of the charge separation in molecules containing atoms of different electronegativities
• Hybridization


  mixing of different orbitals in the same atom to form hybrid orbitals.
• Intermolecular Forces


  the attractive and repulsive forces that arise between the molecules of a substance
• Another name for IMF

  Van de Waals forces
• London Dispersion


  interaction between nonpolar molecules
• Dipole-Dipole


  interaction between polar molecules
• Hydrogen Bonding


  interaction between molecules that contains an O, F, and N atom covalently bonded to a H atom.
• Ion-dipole


  occurs when polar molecules are attracted to ions.