LaMotte SMART 2 Electronic Soil Lab - Manual (Page 55)

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 a * are considered to be potential health hazards. To view
or print a Material Safety Data Sheet (MSDS) for these reagents see MSDS CD or
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.
SMART2 SOIL MANUAL 1.07 55