In terms of a #P-Cl# bond in a molecule of #PCl_5#, why it is more polar than a #P-S# electron bond in a molecule of #P_2S_5#?

1 Answer
Jan 24, 2017

Answer:

The polarity of a bond depends on both atoms involved in the bond. The difference an this case is due to the difference in electronegativity between chlorine and sulfur.

Explanation:

As mentioned above, one must consider the difference in the electronegativities of the two bonded atoms. Chlorine is somewhat more electronegative than sulfur.

Since electronegativity is designed to provide a measure of an atom's ability to draw bonding electrons toward itself, a bond having a greater difference between the atoms will be one in which the sharing of electrons is more unequal, and a greater bond dipole results.

Thus, chlorine is better able to draw electrons away from phosphorus than is sulfur, and the #P-Cl#bond is more polar.