6.21 in textbook [ENDORSED]

[Annabella_Amato_1I]

For this question, why is it that Nitrogen accepts the H+ ions and not the oxygen? Is this because N is more electronegative than O? Also, why would it be considered amphoteric? Thanks!

[Chem_Mod]

Oxygen, as the more electronegative element, holds more tightly to its lone pair than the nitrogen. The nitrogen lone pair, therefore, is more available to form a new bond to a proton. This makes the nitrogen lone pair more basic.

After gaining one H+ it is amphiprotic as one nitrogen can give off H+ and the other nitrogen can pick up H+.

This question could be worded better but I include it in my homework/syllabus as it is a nice biological example.