During an acid-base titration, what do you observe at the equivalence point?

At the equivalence point during an acid-base titration, the amount of acid present in the solution exactly equals the amount of base added. This is a critical moment in the titration, as it indicates that the reaction between the acid and base has reached a stoichiometric balance. At this point, the moles of hydrogen ions (from the acid) are equal to the moles of hydroxide ions (from the base), and they will neutralize each other to form water and a salt.

While other aspects, such as a color change depending on the indicator used, or pH measurement, might be relevant during the titration, they do not accurately define the equivalence point itself. The pH may not necessarily be 7 at the equivalence point for all acid-base combinations; for example, a strong acid and a weak base will have a pH less than 7 at equivalence. Additionally, saturation does not directly relate to the titration in question, as saturation generally refers to the maximum concentration of a solute in solution and is not a defining characteristic of the equivalence point. Thus, the key identifying feature of the equivalence point is the equal stoichiometric amounts of acid and base present.