The equivalence point is reached when the indicator is changed colour.
Some students might be mistaken by choosing the choice B). In fact, the equivalence point is reached when the number of mole of
For example, consider the sulphuric acid (
In this case,
thus, the number of mole of acid is equal to twice the number of mole of base added.
Here is a video that explains titration with more details:
Lab Demonstration | Acid - Base Titration.