LaMotte SMART 2 Electronic Soil Lab User Manual
Page 60
PROCEDURE
Carefully read the LaMotte Direct Reading Titrator Manual (1649) before
performing the titration procedure described below. The Titrator is calibrated
in terms of parts per million chloride and each minor division on the Titrator
scale equals 20 ppm.
1. Fill a clean test tube (0701) to the 15 mL line with deionized water.
2. Add 3 measures of soil using the 1 g spoon (0697). Cap tube and shake for
five minutes.
3. Filter and collect all of the soil filtrate using the funnel (0459) and filter
paper (0463). The extract does not have to be clear since a slight turbidity
does not interfere in the test.
4. Fill the test tube (0778) to the 10 mL line with the filtrate.
5. Add three drops of *Chloride Reagent #1 (4504) to the sample. Cap and
shake to mix. A yellow color will result.
6. Fill the Direct Reading Titrator (0384) with *Silver Nitrate, 0.141
(3062DR) in the manner described in the instruction manual.
7. Titrate the test sample with *Silver Nitrate, 0.141 (3062DR) until the
yellow color changes permanently to pink. Record the Titrator reading. If
the plunger reaches the bottom mark (1000 ppm) on the Titrator scale
before the endpoint color change occurs, refill the Titrator and continue the
titration procedure. Be sure to include the value of the original amount
added (1000 ppm) when recording the final result.
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SMART2 SOIL MANUAL 1.07