How would each of the folowing affect the accuracy of the calculated neutralizing power of the antacid (too high, too low, no effect)? Explain why.

Question

a) Titration flask was wet with distilled water
b) The burette was initally not rinsed with 0.10M NaOH and some water was left in the tip by the previous student
c) The flask was not heated before the titration and when the solution turned pink, there was powder floating on the suface of the solution.

Thanks!

Answer 1

You haven't described the procedure you used; therefore, I don't know if you titrated the antacid tablet(s) directly or if you used a back titration procedure.
Perhaps I can get you started.
a) Titration flask was wet with distilled water will have no effect. Students often say to me, "But the water will dilute the mixture before titration." That is true BUT you dilute everything by the same amount. The CHEMISTRY reason is that you are titrating moles and the water adds no moles of either antacid or base.
b)Not rinsing the buret with NaOH and adding NaOH to a wet buret means you have diluted NaOH. Therefore, you will add more from the buret, it will read higher, the apparent volume of the NaOH will be increased and that will mean moles NaOH is too high. How that affects the results depends upon what kind of procedure was used.
c) I can't comment on c since I don't know the procedure.

Answer 2

No effect
too high
too low