Amino Acid Titration: Why COOH H First?

[lha08]

Homework Statement

Lets say we titrate an amino acid with a strong base (NaOH), like I know that the hydrogen of the carboxyl (COOH) group will be pulled away followed by the amino group (NH3+), but is there a particular reason why the hydrogen on the carboxyl group is pulled out first rather than the amino acid? Does it have to do with the repulsion caused by the NH3+ group that causes the carboxyl hydrogen to come off first?
Thanks.

Homework Equations

The Attempt at a Solution

 

[Borek]

Which is usually a stronger acid - -COOH, or -NH₃⁺?

 

[lha08]

Which is usually a stronger acid - -COOH, or -NH₃⁺?

Is COOH the stronger acid? but then NH₃+ is a weak acid? (i somehow thought that NH₃+ acts as a base...)

 

[Borek]

-NH₂ is a base, -NH₃⁺ is a conjugate acid.

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