What color does chloride indicator change from during titration?

During the titration process involving a chloride indicator, the indicator typically changes from yellow to pink when titrating with silver nitrate. This color change occurs because the chloride ions react with silver ions, forming a precipitate of silver chloride. The transition indicates the concentration of chloride in the solution being tested.

In this context, the yellow color represents the initial state of the solution before any chloride ions are present or have reacted significantly. As titration proceeds and chloride ions are consumed, the excess silver ions ultimately react with the indicator, resulting in a noticeable color shift to pink, which signifies the end point of the titration.

This understanding of the color change is vital for water operators, as it allows them to accurately measure chloride levels, which are important for assessing water quality and ensuring safety for consumption. The other answer choices do not represent common color changes associated with chloride titrations and thus are not relevant in this scenario.