Answer:
a. polar (polar bonds w/ asymmetrical electron distribution
b. non-polar (pure covalent bond, very symmetrical electron distribution
c. non-polar (polar bonds, symmetrical distribution of electrons)
d. polar (polar covalent bonds, asymmetrical electron distribution)
e. non-polar (polar covalent bonds, symmetrical electron distribution)
Explanation:
polarity of a molecule depends on the distribution of electrons within the molecule. If electrons are grouped near one point (an apex of a pyramidal-shaped molecule or at the end of a liner molecule), the molecule will be polar. Even if a molecule is symmetrical (like the tetrahedral carbon molecules) having fluorines attached along with chlorines and hydrogens (CFCl2H) becomes very polar. This is because the very electronegative fluorine atom pulls so strongly on the two electrons its supposed to be sharing (plus the 3 unshared pairs its also has) that the fluorine end of the pyramid is more negative than the hydrogen end. The very symmetrical, linear CO2 molecule with its 2 double bonds has its electrons so uniformly distributed within the molecule that the molecule is not polar at all.
