please help me with acidity scale

[Questions]

Advertisement - Members don't see this ad

What is more acidic, phenol or carboxylic acid??

Destroyer says aromatic acids are more acidic than carboxylic acids, but the ADA practice says carboxylic acid is more acidic. so which one is it?

Thank you

 

[azar87]

I beleive that the phenol is more acidic because the hydroxyl group comming off the aromatic ring has a very acidic proton as compared to the COOH. I would say destroyer is correct here.

 

[dentalWorks]

It depends on what kind of phenol your talking about. A normal phenol (without any e donator / acceptor groups makes its acidity strength different)

Here is a site I found usefull that shows the PKa values of phenol vs a type of carboxylic acid

 

[RSD2014]

What is more acidic, phenol or carboxylic acid??

Destroyer says aromatic acids are more acidic than carboxylic acids, but the ADA practice says carboxylic acid is more acidic. so which one is it?

Thank you

Are you comparing a regular carboxylic acid vs an Aromatic Carboxylic acid?

Strong Acid has a Stable conjugate base.

Aromatic Carboyxylic Acid has a ring that delocalizes electrons stabilizing the conjugate base. Thus, it is a stronger Acid, more acidic.

 

[TexasOMFS]

I'm pretty sure OP means aromatic carboxylic acid (not phenol) because I think I remember this question from when I ran through destroyer.
^Poster above is correct. But if you're comparing a phenol (benzene with an OH group) vs. carboxylic acid, it'll be carboxylic acid in almost all cases no matter what other substituents are on the benzene ring. A phenol is an alcohol which is far less acidic than COOH groups. It would take a LOT of electron withdrawing groups to make the phenol more acidic than the acid.