LaMotte COD Plus Colorimeter 1922-EX2 - Manual (Page 99)

PROCEDURE
1. Use the 10 mL graduated cylinder (0416) to measure 10 mL of sample
water. Pour into glass test tube (0608).
2. Use the 1 mL pipet (0354) to add 1 mL of *Hydrochloric Acid, 2.5N
(6251).
3. Use the 0.1 g spoon (0699) to add 2 measures of *Ammonium Persulfate
Reagent (6566). Add two drops of *Silver Nitrate Solution, 0.0141N
(6346WT). Mix until the powder has dissolved. The solution will be
slightly cloudy at this point.
4. Use 10 mL graduated cylinder (0416) to add 5 mL of Sodium Citrate, 10%
(6253).
5. Use a second 1 mL pipet (0354) to add 1 mL of *Ammonium Hydroxide,
Conc. (6537). Mix, then dilute to 25 mL with deionized water.
6. Use a third 1 mL pipet (0354) to add 1 mL of *Dimethylglyoxime, 1%
(6254). Mix. Wait 20 minutes for color development.
7. At end of 20 minute waiting period fill a clean tube (0290) to the 10 mL
line with the developed test sample.
8. Fill a second clean tube (0290) to 10 mL line with deionized water or
untreated sample water. This is the blank.
9. Press and hold ON button until colorimeter turns on.
10. Press ENTER to start.
11. Press ENTER to select TESTING MENU.
12. Select ALL TESTS (or another sequence containing 17 Nickel) from
TESTING MENU .
13. Scroll to and select 17 Nickel from menu.
14. Insert the blank into chamber, close lid and select SCAN BLANK.
15. Insert test sample into chamber, close lid and select SCAN SAMPLE.
Record result.
16. Press
OFF button to turn colorimeter off or press EXIT button to exit to a
previous menu or make another menu selection.
NICKEL 2/2 COD PLUS TEST PROCEDURES 6/02