Glycolic acid functional group(s)

[shihab-kol]

Hey guys, should the -OH group in glycolic acid be considered a functional group or a substituent due to the presence of the carboxylic acid group?

 

[TeethWhitener]

a functional group or a substituent

What, in your view, is the difference? And how would the presence of a carboxyl group make a difference?

 

[James Demers]

It's a "substituent" under most naming conventions, but chemically it's a functional group. Glycolic acid is difunctional.

 

[jim mcnamara]

Some links:
https://en.wikipedia.org/wiki/Functionality_(chemistry)

Nice graphics:
http://preparatorychemistry.com/Bishop_Jmol_difunctional.htm