This kit uses titrations with standard acid to the phenolphthalein (P) and total (T) alkalinity endpoint. Where hydroxyl (OH) alkalinity is determined directly, the sample is penetrated with barium to precipitate carbonates. All results are expressed as CaCO3 and this test kit contains 50 tests to 200ppm.
To qualify as an EPA accepted test and to achieve greatest accuracy, the normality of the *Alkalinity Reagent B should be checked periodically. Standardize *Alkalinity Reagent B by titrating against 0.05N Na2CO3; 1 mL = 1.00 mg CaCO3. Should a variance of greater than 0.3 mL of *Alkalinity Reagent B occur, discard and order a fresh bottle of *Alkalinity Reagent B (Code 4493DR-H). A CaCO3 equivalent standard of 100 ppm is also available (Code 6199-H). Refer to Standard Methods, 16th edition, 403, 1985.
1. Fill test tube (0778) to 5 mL line with sample water.
2 Add two drops of *Alkalinity Indicator # 1 (3870). Cap and mix. If a red color develops, P alkalinity is present. Proceed to Steps 3-5. If no red color develops, P alkalinity is not present. Proceed to Step 3 and then skip to Total Alkalinity Procedure Steps 6-9.
3. Fill Direct Reading Titrator with *Alkalinity Reagent B (4493). Insert Titrator in center hole of test tube cap.
4. While gently swirling tube, slowly depress plunger until red color disappears. Record test result where plunger tip meets titrator scale. Record as P Alkalinity in ppm CaCO3. EXAMPLE: Plunger tip is 3 minor divisions below 80 line. The test result is 80 + (3 x 4) = 92 ppm, since each division is equal to 4 ppm.
5. If plunger tip reaches the bottom line on the titrator scale (200 ppm) before the endpoint color change occurs, refill Titrator and continue titration. When recording test result, include original amount of reagent titrated (200 ppm). NOTE: Do not move the titrator plunger after P Alkalinity endpoint has been obtained.
6. Without moving plunger, remove Titrator and test tube cap from test tube containing sample from Step 4.
7. Add two drops Alkalinity Indicator #2. Cap and swirl to mix. A blue color will appear. Insert Titrator in center hole of test tube cap.
8. While gently swirling tube, slowly depress plunger until blue color changes to green. Record test result as T Alkalinity in ppm CaCO3. Include total amount of titration reagent added. (See Step 5).
9. If only Total Alkalinity is to be tested, perform Steps 1, 7 and 8 only, using a full titrator for Step 8.
Unit Ship Weight: 1 lb