Chem 111 Chp 8

  1. Addition Compounds
    A molecule formed by the joining of two simpler molecules through formation of a covalent bond
  2. Bond Energy
    The energy needed to break one mole of a particular bond to give electrically neutral fragments. Increases and bond length decreases.
  3. Bond Length
    The distance between two nuclei that are held together by a chemical bond.
  4. Bond Order
    # of bonding pairs of e- divided by the # of stoms bonded to central atom
  5. Carboxyl Group
    —CO 2H
  6. Carboxylic Acid
    An organic compound whose molecules have the carboxyl group —CO 2H
  7. Contributing Structures
    One of a set of two or more Lewis structures used in applying the theory of resonance to the structure of a compound. A resonance structure.
  8. Coordinate Covalent Bond
    A covalent bond in which both electrons originated from one of the joined atoms, but otherwise like a covalent bond in all respects.
  9. Covalent Bond
    A chemical bond that results when atoms share electron pairs EN < 1.7
  10. Dipole Moment
    The product of the sizes of the partial charges in a dipole multiplied by the distance between them; a measure of the polarity of a molecule.
  11. Double Bond
    A covalent bond formed by sharing two pairs of electrons.
  12. Electric Dipole
    Two poles of electric charge separated by a distance
  13. Electronegativity
    The relative ability of an atom to attract electron density toward itself when joined to another atom by a covalent bond.
  14. Formal Charge
    The apparent charge on an atom in a molecule or polyatomic ion as calculated by a set of rules.
  15. Ionic Bond
    The attractions between ions that hold them together in ionic compounds.
  16. Ionic Character
    The extent to which a covalent bond has a dipole moment and is polarized.
  17. Lattice Energy
    Energy released by the imaginary process in which isolated ions come together to form a crystal of an ionic compound.
  18. Lewis Formula
    A structural formula drawn with Lewis symbols and that uses dots and dashes to show the valence electrons and shared pairs of electrons.
  19. Nonpolar Covalent Bond
    A covalent bond in which the electron pair(s) are shared equally by the two atoms. EN = 0
  20. Octet of Electron
    Eight electrons in the valence shell of an atom.
  21. Octet Rule
    An atom tends to gain or lose electrons until its outer shell has eight electrons.
  22. Partial Charges
    Charges at opposite ends of a dipole that are fractions of full 1+ or 1- charges
  23. Polar Covalent Bonds
    A covalent bond in which more than half of the bond's negative charge is concentrated around one of the two atoms. EN < 1.7
  24. Polar Molecule
    A molecule in which individual bond polarities do not cancel and in which, therefore, the centers of density of negative and positive charges do not coincide
  25. Reactivity
    A description of the tendency for a substance to undergo reaction. For a metal, it is the tendency to undergo oxidation.
  26. Resonance
    • A concept in which the actual structure of a molecule or polyatomic ion
    • is represented as a composite or average of two or more Lewis
    • structures, which are called the resonance or contributing structures
    • (and none of which has real existence)
  27. Resonance Energy
    The difference in energy between a substance and its principal resonance (contributing) structure.
  28. Resonance Hybrid
    The actual structure of a molecule or polyatomic ion taken as a composite or average of the resonance or contributing structures.
  29. Resonance Structure
    A Lewis structure that contributes to the hybrid structure in resonance-stabilized systems; a contributing structure
  30. Single Bond
    A covalent bond in which a single pair of electrons is shared.
  31. Structural Formula
    • A chemical formula that shows how the atoms of a molecule or polyatomic
    • ion are arranged, to which other atoms they are bonded, and the kinds of
    • bonds (single, double, or triple).
Card Set
Chem 111 Chp 8
Chemistry Final