Chemistry ch 14

  1. ionic crystals are held together by
    the attraction of positive ions and negative ions
  2. what forces hold the atoms in molecules together?
    • intramolecular forces
    • (not electrically charged ions)
  3. polarity
    • Different EN's, so there isn't equal sharing of shared pairs
    • The highest EN attracts the shared pair more strongly and causes that end to have a partial negative charge.
    • The other end is partial pos, causiong a polar molecule
  4. In most cases, polar covalent bonds produce what kind of molecules?
    Polar molecules
  5. A polar molecule is often called a
    dipole/dipole moment
  6. u=
    Q x d
  7. What does a high dipole moment mean?
    the intramolecular forces in a molecule are strong, resulting in a higher MP and BP
  8. Can polar covalent bonds be present in a nonpolar molecule? Why?
    • Yes
    • The symmetry is key
  9. Weak forces
    intermolecular forces (between 2 molecules) and act to hold 2 or more molecules together
  10. van der Waals forces
    the attraction of an electron from 1 atom and the proton froma second atom
  11. dipole-dipole forces
    occur when 2 molecules that normally are dipoles attract
  12. dipole-induced dipole forces
    occur when a dipole attracts a nonpolar molecule by inducing this molecule to form a temporary dipole
  13. dispersion or London forces
    occur when 2 nonpolar molecu;es attract because of the random movement of their electrons
  14. molecules held by weak forces tend to be
    • gases
    • low BP liquids
  15. ligands are what kind of molecules/have what charges?
    • polar molecules- no charge
    • or negative ions
  16. complex ion
    when ligands cluster around the central positive ion
  17. coordination number
    number of points of attachment
  18. Most common coordination number
    • 6
    • octahedral
  19. coordination 4
    • square planar
    • Ni, Pd, Pt, CO
  20. coordination 2
    • always linear
    • formed with positive ions
    • Ag, Au, Hg
  21. didentate
    • ligand attaches to the central positive atom at 2 spots
    • oxalato
  22. molecular ligands are always
    • polar
    • have at least one unshared pair
    • ammonia
  23. which names change to latin?
    • Cu
    • Au
    • Ag
    • Fe
    • Pb
    • Sn
  24. coordination compound
    • form when complex ions are involved in the formation of a compound.
    • 3 ways
  25. 1st way to form coordination compound
    the charge of the positive ion is equal to the total charges of the ligands
  26. 2nd way to form a coordination compound
    neither the atom nor the ligands have a charge
  27. 3rd and most common way to form a coordination compound
    complex ions form a compound with 1 or more monoatomic, polyatomic, or complex ion of the opposite charge
Card Set
Chemistry ch 14
polar molecules and molecular attraction