Calcium & magnesium – LaMotte SMART 3 Electronic Soil Lab User Manual
Page 59
SMART3 Soil 1.11
59
CALCIUM & MAGNESIUM
SCHWARZENBACH EDTA METHOD • CODE M-CAL-MAG
QUANTITY
CONTENTS
CODE
30 mL
*Calcium & Magnesium Buffer
*5126-G
60 mL
Standard EDTA Reagent
5254-H
100
Calcium Hardness Indicator Tablets
T-5250-J
30 mL
Calcium Magnesium Inhibitor Reagent
3922-G
30 mL
*CM Indicator Reagent
*6522WT-G
30 mL
*Sodium Hydroxide w/Metal Inhibitors
*4259-G
15 mL
*Inhibitor Solution
*9258-E
15 mL
*TEA Reagent
*3921-E
2
Direct Reading Titrators, 0-1000 Range
0384
1
Pipet, transfer, plastic
0364
1
Test tube, 5-10-15 mL, glass, w/cap
0778
*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.
The amount of total calcium in soils may range from as little as 0.1% to as much
25%. A calcium deficiency is rarely a problem due to widely accepted practice
of applying lime to soil to raise the pH to the proper range for optimum plant
growth. As an important mineral nutrient, calcium is a component of cell walls in
plants and is known to stimulate root and leaf development as well as activate
several enzyme reactions involved in plant metabolism. Indirectly, calcium
influences crop yields by reducing soils acidity and by reducing the toxicity of
several other soil minerals such as manganese, zinc, and aluminum.
The Schwarzenbach EDTA titration method, used to determine calcium and
magnesium, involves two titrations. The first titration gives the calcium and
magnesium content, the second only calcium. Magnesium is calculated from
the difference between the titration values.
RANGE:
0-4000 lb/acre Calcium
0-2400 lb/acre Magnesium
METHOD:
Titration with Schwarzenbach EDTA
INTERFERENCE: Sample color and turbidity may interfere with endpoint.
Test P
rocedures