LaMotte Greenhouse Soil Testing Outfit GS-01 - Manual (Page 4)

USE OF THE OCTET COM PARA TOR
The Octet Comparator contains eight permanent
color standards. A test sample is inserted into the
openings in the top of the comparator. The sample
can then be compared to four color standards at
once, and the value read off the comparator. For
optimum color comparison, the comparator should
be positioned between the operator and a light
source, so that the light enters through the special
light-diffusing screen in the back of the comparator.
Avoid viewing the comparator against direct
sunlight or an irregularly lighted background.
AC CES SORIES
QUANTITY CONTENTS CODE
1 Demineralizer Bottle 1155
1 Graduated Cylinder, 25 mL, glass 0417
6 Syringes, 60 mL, plastic 0943
6 Beakers, 50 mL, plastic 0944
2 x 100 Filter Papers, 2.5 cm 0947
1 Extraction Stand 1110
To order individual reagents or test kit components, use the specified code
number.
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PRO CE DURE
DI LU TION OF SOIL EX TRACT
1.
Use the graduated cylinder (0417) to transfer 10 mL of soil extract
to a 50 mL beaker (0944).
2. Use the graduated cyliner (0417) to add 10 mL of deionized water.
Mix.
TI TRA TION A: CAL CIUM & MAG NE SIUM
1.
Fill test tube (0778) to 5 mL line with diluted soil extract. Dilute to
10 mL line with deionized water.
2. Add 5 drops of Calcium-Magnesium Inhibitor Reagent (3922). Swirl
to mix. Wait 5 minutes.
3. Add 5 drops of *Calcium & Magnesium Buffer (5126). Swirl to mix.
4. Add 10 drops of *CM Indicator (6522). Swirl to mix. Solution will
turn red.
5. Fill the Direct Reading Titrator (0384) with Standard EDTA
Reagent (5254). Insert Titrator tip into the center hole of the test
tube cap.
6. While swirling the tube, slowly press the plunger to titrate sample
until color changes from red to blue.
7. Read the result where the plunger tip meets the scale. Multiply by
5.16. Record as Value A.
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