[rproctor]

A buffer is made by adding some NaH2PO4 to a solution of H3PO4

a) write the balanced equation that describes the chemical equilibrium for this system
b) Identify weak acid
c) Identify the conjugate base of the weak acid
d) what is the pKa for this system

My answers
a) H3PO4(aq) + H20(l) <--> H2PO4- (aq)+ H3O+(aq)
b)H3PO4
c)H2PO4-
d) pKa=2.12


I'm not sure if I am going about answering this problem the correct  way.

[Pradeep]

It looks like correct for me.