What color transition indicates a successful titration for chloride?

The transition from yellow to pink during a titration for chloride indicates a successful endpoint. This color change occurs due to the presence of an indicator, typically used in titrations for halides, such as silver nitrate solutions, where the indicator changes color when all chloride ions have reacted. As the titration progresses, the solution begins as yellow, showing the presence of chloride ions, and when sufficient titrant has been added to bind with all the chloride, the solution shifts to pink, indicating the new equilibrium state.

This specific color transition is essential for ensuring that the correct amount of titrant has been added and that the reaction is complete. Understanding this transition is crucial for water operators conducting tests to meet compliance and maintain water quality standards, as it provides an accurate measure of chloride concentration in the sample.