6.7 Electronegativity and Bond Polarity

6.7 Electronegativity and Bond Polarity

  • The polarity of a bond can be determined using electronegativity.
  • Bonding electrons are shared between atoms, so we can learn more about the chemistry of compounds.
    • The bonding electrons are the same as the nonmetal atoms.
    • The electron pairs are usually shared equally when a bond is between atoms.
    • The electrons in the bond are attracted to one atom more than the other.
  • Nonmetals have higher electronegativities than metals.
  • The attraction of fluorine for shared electrons is the reason for the electronegativity.
    • The lowest electronegativity value of 0.7 can be found in the lower chlorine atom of the periodic table.
  • Try Practice Problems 6.61 to 6.64 are not included in our discussion because of the low electronegativity values for transition elements.
  • A decrease going down a group.
  • Predicting the type of chemical bond, ionic or covalent, can be done with the difference in the electronegativity values of two atoms.
    • The electronegativity difference is zero, which means the bonding electrons are shared equally.
  • We drew a symmetrical electron cloud around the H atoms.
    • The cloud for a bond is notsymmetrical.
    • When finding the electronegativity difference, the smaller electronegativity is always subtracted from the larger; thus, the difference is always a positive number.
  • The electrons are shared equally.
    • The electrons are shared equally in the bond.
  • The atom with the lower electronegativity becomes partially positive because of the lack of electrons at that atom.
  • The arrow points from the positive charge to the negative charge to indicate the dipole.
  • There is no definite point at which one type of bond stops and the next starts.
    • The H bond is classified as nonpolar covalent bonds.
  • If you use electronegativity differences strongly, you can increase the polarity of the bond.
    • The H bond is classified as a polar covalent bond.
  • The electronegativity difference for the ionic compound is 3.0.
  • The values are taken from Figure 6.6.
  • The difference in electronegativity is calculated for each bond.