It says on google <span>An acid-base indicator (e.g., phenolphthalein) changes color depending on the pH. Redox indicators are also frequently used. A drop of indicator solution is added to the titration at the start; when the color changes the endpoint has been reached, this is an approximation of the equivalence point.</span>
Titration is a method of quantitative analysis which is employed to determine the concentration of unknown solutions.
Here a titrant of known concentration is added to a given volume of an analyte solution along with a suitable indicator. The titrant is added gradually until a color change in the analyte is observed. This point is known as the end point.
The end point is usually approximated as the equivalence point wherein the moles of titrant consumed equals the moles of analyte present.
