I do not know how to rank the polarity between these, i have also included the boiling point in degrees C but it still does not help. The only thing that i think is that D is the least polar because it is symmetrical, and i think A is the most but I'm not sure about the rest. Thank you for your help!

Question

Rank order of polarity from least to greatest:
A) benzoic acid 246.2
B) benzaldehyde 178.1
C) benzyl alcohol 205
D) Naphthalene 218

Answer 1

Here is a good web site.
http://www.elmhurst.edu/~chm/vchembook/213organicfcgp.html

Here is the line you should focus on.
Amide > Acid > Alcohol > Ketone ~ Aldehyde > Amine > Ester > Ether > Alkane