LaMotte AST Series Professional Soil Test Outfits - Manual (Page 26)

COPPER
Copper acts as a catalyst in enzyme systems. In acidic soils, aluminum
may compete with copper, resulting in decreased uptake by plants. The
balance of copper with iron and molybdenum may be more important
than the actual amounts present in the plant.
A Standard Color Solution is added to an untreated sample until it
matches the color of the sample in which the copper has reacted with
sodium diethyeldithiocarbamate in the Copper Reagent.
QUANTITY CONTENTS CODE
2 x 15 mL *Copper 1 Reagent *6446-E
2 x 15 mL Copper 2 Reagent 6613-E
2 Test tubes, plastic, w/cap 0106
1 Sheet, white, plastic 32961
*WARNING: Reagents marked with an * are considered to be potential health
hazards. To view or print a Material Safety Data Sheet (MSDS) for these
reagents go to www.lamotte.com. To obtain a printed copy, contact LaMotte by
e-mail, phone or fax.
PROCEDURE
1.
Fill two test tubes (0106) to the 10 mL line with neutralized soil
extract.
NOTE: See Neutralization of Soil Extract, page 15.
2. Add 5 drops of *Copper Reagent (6446) to one test tube. Cap and
mix. Remove cap.
3. Hold both test tubes one-half inch above the white plastic sheet.
The extract with the reagent will appear yellow if copper is present.
4. Add Copper 2 Reagent (6613) to the second, untreated sample, one
drop at a time, with mixing, until the color of the two samples is the
same. Count the number of drops added. Hold bottle vertically.
5. Multiply number of drops of Copper 2 Reagent used in Step 4 by
0.25. Record as ppm Copper.
1 ppm = 4 drops
2 ppm = 8 drops
3 ppm = 12 drops
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