User manual HANNA INSTRUMENTS HI 38076

[. . . ] Please read the instruction sheet carefully before using the test kit. It will provide you with the necessary information for correct use of the kit. If you need additional information, do not hesitate to e-mail us at tech@hannainst. com. [. . . ] By gently 20 mL squeezing the bottle, add demineralized water to the other vial up to the 20 mL mark. 6- Remove the cap, add 1 packet of HI 93731A-0 reagent. Replace the cap and mix the solution until the powder has completely dissolved. CHEMICAL REACTION Zinc reacts with the zincon reagent to form a brownishgreen complex 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 brown-violet colored product. The amount of color developed is proportional to the concentration of zinc present in the aqueous sample. 7- Using the long plastic pipette, remove 10 mL of the orange solution and dispose of it (the level of the remaining liquid in the vial has to correspond to the 10 mL mark). 8- Add 1 mL of HI 93731B-0 reagent to the vial, using the syringe. Note: To measure exactly 1 mL of reagent with the syringe, push the plunger completely into the syringe and insert the tip into reagent bottle. Pull the plunger out until the lower edge of the seal is on the 0. 0 mL mark of the syringe. Insert the syringe into the vial and push the reagent out until the lower edge of the seal is on the 1. 0 mL mark. 9- Replace the cap and mix for 15 seconds. Wait for 3 and a half minutes to allow color to develop. Note: the sample is turbid, but this thing does not affect the measurement. 10- Remove the cap and insert the reacted sample into the right hand opening of the checker disc. 11- Hold the checker disc so that a light source illuminates the samples from the back of the windows. It is better to match the color with a background uniform and light in color (e. g. [. . . ] Follow the procedure from step 6 to step 12. 17- Multiply the reading value by 5 to obtain mg/L (ppm) of Zinc. 18- Discard the reacted sample after measurement, because the glass might become permanently stained. [. . . ]