Calculate the pH of a solution that contains the following analytical concentrations: (a) 0.225 M in H3PO4

Question:

Calculate the pH of a solution that contains the following analytical concentrations:
(a) 0.225 M in H3PO4 and 0.414 M in NaH2PO4.
(b) 0.0670 M in Na2SO3 and 0.0315 M in NaHSO3.
(c) 0.640 M in HOC2H4NH2 and 0.750 M in HOC2H4NH3Cl.
(d) 0.0240 in H2C2O4 (oxalic acid) and 0.0360 M in Na2C2O4.
(e) 0.0100 M in Na2C2O4 and 0.0400 M in NaHC2O4.