Question

If the endpoint is surpassed in a back titration with NaOH, will the reported amount of antacid in the sample be too high or too low? Explain

Answer 1

Answer:

too low

Explanation:

Antacids are essentially bases. For the experiment,  the antacid samples are dissolved in an excess acid like HCl, the unneutralized HCl is then back titrated with NaOH of a known concentration.

Moles of antacid is sample = Initial moles of the excess HCl - moles of HCl neutralized by NaOH   -----------(1)

If the end point is surpassed in the  back titration, this implies that the moles of HCl neutralized by the acid will be a higher value. Based on equation (1), this situation would result in a lower value of the moles of antacid in the sample. Hence, amount of antacid in the sample would be too low.

Answer 2

  It throws it off, you have to re-do the experiment. The NaOH M will be higher because you poured to much inside and made it pink!