Polarity

DanielDaniels

Which is more polar and why?

polarity.PNG4.4KB

Reply 1

Kallisto

Entertainment Forum Helper

You have three different positions of nitrophenol, meta-position (in the middle), para-position (right) and ortho-position (left). If I am not mistaken the polarity of an aromatic compound is stonger the closer two functional groups are to each other. Thus it must be the left nitrophenol with the strongest polarity, as it has the ortho-position and in this position the functional gropus (OH and NO2 in this case) are very close to each other, closer than the other functional groups.

So it is this order: ortho > meta > para

Refer to the picture it is: left > middle > right

Reply 2

Pigster

OH is e- donating and NO2 is withdrawing.

Wouldn't opposite set up a dipole?

Reply 3

username913907

Original post by Pigster

OH is e- donating and NO2 is withdrawing.

Wouldn't opposite set up a dipole?

I think the inductive effects are more important, so I believe the o>m>p order is correct.

Reply 4

Kallisto

Entertainment Forum Helper

Original post by Pigster

OH is e- donating and NO2 is withdrawing.

Wouldn't opposite set up a dipole?

I thought that the close togetherness of these functional groups would cause a strong negative inductive effect, so many electrons are moved within the aromate, and that would lead to a high polarity...