Titrations WB/SA
1. 100.0ml of a 0.2M solution of NH3 is titrated with a 0.15M HCl solution. Which solution goes into the buret?
Which goes into the beaker? Kb = 1.8 x 10-5
Calculate the pH as various amounts of HCl are added:
a. 0ml HCl
b. Write the net ionic equation for the reaction of NH3 and HCl
c. 5.0ml 0.15M HCl
d. 50.0ml 0.15M HCl
e. 67.0ml 0.15M HCl
f.
133.0ml 0.15M HCl
2. A 50.0ml sample of a 0.224M sodium lactate (NaLac) solution Ka = 1.4 x 10-4. is titrated with a .1035M HCl
solution.
a. Write the net ionic equation for this reaction.
b. What is the initial pH of the NaLac solution before adding any HCl?
c. How much HCl is needed to reach the ½ equivalence point?
d. What is the pH at the ½ E.P.?
e. How much HCl is needed to reach the equivalence point?
f.
What is the pH at the E.P.?