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Specialty Chemistry Forums => Biochemistry and Chemical Biology Forum => Topic started by: Creflo on August 27, 2015, 06:10:38 PM

Title: What is wrong with my identification of these functional groups?
Post by: Creflo on August 27, 2015, 06:10:38 PM
I'm assuming the ester is incorrect, but I don't see how it's a carboxyl group as there is no H attached to the O (the Oxygen has an extra lone pair giving it a negative charge right?) I know this is simple, but any help would be appreciated.  :P  UPDATE: I'm assuming that since COO- is carboxylate that it is indeed a carboxyl group?

(https://www.chemicalforums.com/proxy.php?request=http%3A%2F%2Fi.imgur.com%2FN2j0LQS.jpg&hash=e6983da922a17738f9249428210bd679d0d11e64)

UPDATE: ok so apparently I was right, it is a carboxyl group, I would just delete this post if I could but whatevs. Sorry I'm so dumb!

(https://www.chemicalforums.com/proxy.php?request=http%3A%2F%2Fi.imgur.com%2FzkRJ1Vz.jpg&hash=fccdaf351e10bc163653555333e0fafad04fc749)
Title: Re: What is wrong with my identification of these functional groups?
Post by: Yggdrasil on August 27, 2015, 06:28:06 PM
A carboxyl group (also known as a carboxylic acid) can exist as in a protonated form R-COOH and a deprotonated form R-COO- depending on the pH of the solution.  This is similar to the amino group which also undergoes acid-base chemistry, and a primary amine can either be protonated (R-NH3+) or deprotonated (R-NH2).
Title: Re: What is wrong with my identification of these functional groups?
Post by: Creflo on August 27, 2015, 06:31:33 PM
I figured it out. But thank you for the reply Yggdrasil!
Title: Re: What is wrong with my identification of these functional groups?
Post by: Babcock_Hall on August 27, 2015, 07:21:15 PM
I usually call the conjugate base form a carboxylate group, and the conjugate acid form a carboxylic acid group.