Please review the three chapters of this section:
Acid-base Basic Concepts
Evaluating Acid-base status using the Davenport diagram
Anion Gap
The following publication is a very interesting discussion, but it is not included in the knowledge that is intended to be taught.
Ammonia Transporters and Their Role in Acid-Base Balance
I. David Weiner, Jill W. Verlander
Physiological Reviews Published 1 February 2017 Vol. 97 no. 2, 465-494 DOI: 10.1152/physrev.00011.2016