POTASSIUM CHROMATE, 5% w/v

Potassium Chromate, 5% w/v is an indicator solution for the determination of chloride in urine samples. It is used in argentometric titration, in which chloride ions are determined quantitatively with standard silver nitrate solution.
The test involves a reaction between chloride ions in urine and silver nitrate to give a precipitate of silver chloride. As the reaction progresses the available chloride ions are consumed. When all the chloride has been precipitated the excess silver nitrate reacts with the potassium chromate in the solution.
The silver chromate thus formed is precipitated as a reddish precipitate. The color change indicates that the titration is complete and the chloride concentration in the urine sample can then be calculated.
It is supplied as a clear, lemon-yellow liquid. It has a pH range of 9.5-10.0 and assay requirement of 4.8-5.2%.
The indicator is potassium chromate, not a reacting substance. The accuracy of the results depends on proper titration technique, correct concentration of reagent and clear observation of the end point. The solution should be treated in accordance with the established laboratory procedures so that it remains suitable for analysis.

Used as an indicator solution in argentometric titration for estimating chloride levels in urine samples.