During acid-base titration, what titrant is added to the sample?

In acid-base titration, the titrant is a solution of known concentration that is added to the sample in order to determine the concentration of an unknown solution. In a typical setup, the titrant is contained in a buret, which allows for precise control of the volume of the titrant that is dispensed into the sample being analyzed.

Using a buret is essential during titration because it provides a calibrated measure of volume, which is critical when the goal is to achieve an endpoint where the acid and base have completely reacted. The ability to slowly and accurately add the titrant ensures that the titration can be stopped precisely at the endpoint, often indicated by a color change thanks to an appropriate indicator.

The other options—pipet, volumetric flask, and Erlenmeyer flask—are used in different capacities within the laboratory context but are not directly responsible for delivering the titrant. A pipet is typically used to measure a specific volume of the sample solution, while a volumetric flask is used for preparing solutions to a precise volume. An Erlenmeyer flask is usually employed to hold the solution being titrated, but it does not provide the controlled dispensing of the titrant itself.

Thus, the buret's specific