Question

(1) A 40.0 mL sample of 0.134 M HNO2 is titrated with 0.262 M KOH. (Ka for HNO2 is 4.57×10−4.) Determine the pH at the equivalence point for the titration of HNO2 and KOH

(2) Consider the titration of a 25.0-mL sample of 0.110 M HC2H3O2 with 0.130 M NaOH. (The value of Ka for HC2H3O2 is 1.8×10−5.) Determine the pH after adding 4.0 mL of base beyond the equivalence point.

(3) Consider the titration of a 25.0-mL sample of 0.175 M CH3NH2 with 0.145 M HBr. (The value of Kb for CH3NH2 is 4.4×10−4.) (a) Determine the pH at one-half of the equivalence point. (b) Determine the pH after adding 5.0 mL of acid beyond the equivalence point.