Question

Rank the following titrations in order of increasing pH at the equivalence point of the titration (1 = lowest pH and 5 = highest pH).

100.0 mL of 0.100 M C₂H₅NH₂ (K_b = 5.6 x 10^-4) by 0.100 M HCl

100.0 mL of 0.100 M HF (K_a = 7.2 x 10^-4) by 0.100 M NaOH

100.0 mL of 0.100 M HC₃H₅O₂ (K_a = 1.3 x 10^-5) by 0.100 M NaOH

200.0 mL of 0.100 M H₂NNH₂ (K_b = 3.0 x 10^-6) by 0.100 M HCl

100.0 mL of 0.100 M KOH by 0.100 M HCl

Answer 1

1) 200.0 mL of 0.100 M H2NNH2 (Kb = 3.0 x 10-6) by 0.100 M HCl

2)  100.0 mL of 0.100 M C2H5NH2 (Kb = 5.6 x 10-4) by 0.100 M HCl

3)  100.0 mL of 0.100 M KOH by 0.100 M HCl

4) 100.0 mL of 0.100 M HF (Ka = 7.2 x 10-4) by 0.100 M NaOH

5) 100.0 mL of 0.100 M HC3H5O2 (Ka = 1.3 x 10-5) by 0.100 M NaOH

for weak base and strong base titration equivalent point pH will be lessthan 7.

for weak acid and strong base titration equivalent point pH will be greater than 7.

strong acid and strong base titration equivalent point Ph =7