Does phtalic acid have a permanent dipole? What about terephtalic acid?

Question

I would really apreciate if you could answer this question and explain the answer to me.
An anticipated thank you!

Answer 1

phthalic acid does have a permanent dipole because the molecule is not symmetrical and the different electronegativities between carbon and oxygen. The COOH group will be slightly -ve and the rest of the molecule will be slightly +ve.

terephthalic acid (a principal component in the production of polyester) will also have a dipole but much weaker than phthalic acid. Both COOH groups will be slightly negative but not as negative as the phthalic acid because the COOH groups are on opposite sides of the molecule and they end up fighting over the electrons in the middle so neither side gets as many electrons as they would if they were separte.