Question

For questions 9 and 10, suppose the titration solution questions 6-8 had involved 5.00 mL of 0.450 M
HBrO instead of HBr.
9. (3 pts) True or False? The volume of 0.120 M NaOH needed to reach the equivalence
point would be the same for 0.450 M HBr or 0.450 M HBrO.________
10. (5 pts) Which titrated solution should have the lower pH at the equivalence point, 0.450
M HBrO or 0.450 M HBr? Briefly explain your answer.
4
For questions 11-13, consider a 1.00 L solution at 25˚C containing both 0.0020 M Ba2+ and
0.0020 M Pb2+.
11. (5 pts) A solution containing dissolved SO42– is slowly added to the solution above. Which
salt will precipitate first, BaSO4 or PbSO4? Briefly explain your answer.

Formula KSP

BaSo4 1.1x10^-10

PbSO4 6.3x10^-7

Answer 1

9.HBr is a strong acid than HBrO therefore it will generate more no. of H+ ions in solution therefore it require large volume of NaOH solution then HBrO.

So False.

10.HBr is a strong acid than HBrO therefore it at equivalence point it will be having more H+ ions which lead to decrease in pH [ pH =- log (H+) ]

titrated solution that has  lower pH at the equivalence point will be HBr.

11.Ksp (Solubility product constant) is the equilibrium between a solid and its respective ions in a solution. The value of the solubility constant determines the degree to which the compound can dissociate in water. the higher the Ksp the more soluble the compound is.

PbSO4 has higher Ksp value i.e 6.3x10^-7. therefore it will remain in the solution And BaSO4 will precipitate first