The HI3854-100 are high quality reagents that are pre-measured, allowing for users to achieve fast and accurate zinc measurements with the chemical test kit. These reagents follow an adaptation of the zincon method to determine zinc concentration.
For determination of zinc, a reaction with the zincon reagent to form a brownish- green to blue complex occurs in a solution buffered at alkaline pH. Since other metals can form colored complexes with zincon, cyanide is added to complex zinc and any other heavy metal present. Then, cyclohexanone is added to selectively free zinc from its cyanide complex so that it can react with zincon to form the final blue colored product. The amount of color developed is proportional to the concentration of zinc present in the aqueous sample. When one packet of the HI3854A reagent is first added and mixed and then 0.5mL HI93731B reagent is added and mixed for 15 seconds, after a 3.5 minute reaction time, the reaction between zinc and the reagent causes the blue colored complex to form; the greater the concentration, the deeper the color. These reagents are designed to be used with samples that have an expected range of 0.0 to 3.0 mg/L (ppm) zinc.