Question

If you stop a titration just BEFORE the equivalence point, would the calculated concentration be higher or lower than the real concentration? Explain your answer.

a. Higher; excess titrant affects accuracy.

b. Lower; insufficient titrant leads to underestimation.

Answer 1

Stopping a titration before the equivalence point results in a lower calculated concentration of the analyte since insufficient titrant has been added to react completely with the analyte.

Step-by-step explanation:

If you stop a titration just BEFORE the equivalence point, the calculated concentration would be lower than the real concentration. The reason for this is that the titration has not reached the point where the moles of titrant added from the burette are stoichiometrically equivalent to the moles of analyte present in the solution. Stopping early means that insufficient titrant has been added, leading to an underestimation of the analyte's concentration.

Different indicators are used to signal the endpoint of a titration, which should closely coincide with the equivalence point. The proper choice of indicator is crucial for the accuracy of the titration.