[DelquesOtaku]

Excuse me, but could you guys please explain whether the following compounds are polar or nonpolar, and WHY?


-Salt Peter (Potassium Nitrate)
-Aspirin (2-acetyloxybezoic acid)
-Table Sugar (Sucrose)
-Road Salt (Calcium Chloride)
-Antifreeze (Ethylene-glycol)



And how could they possibly relate to electronegative difference? Like for instance with aspirin when we do electronegative difference we do:
O 3.5     O 3.5      C 2.5    C 2.5
C 2.5      H 2.1      H 2.1    C 2.5
-----     ------     ------   ------
1.0         1.4         0.4        0.0

In our charts it tells us that anything above 0.5 is polar, and below 0.5 is nonpolar. How can Aspirin have both nonpolar and polar properties?

Thank you

[Astrokel]

You can't calculate polarity through bonds one by one. It is tedious for complicated molecules. The best way is to look at different functional groups. For example, aspirin has carboxylic, ester and aromatic benzene functional group. Which of it is polar and which is not?