Hanna Instruments HI 83200-01 User Manual
Page 32

62
63
Hardness Mg
• Fill both cuvettes up to the 10 mL mark.
• Add 1 drop of HI 93719C-0 EDTA solution to one cuvette (# 1),
replace the cap and invert the cuvette several times to mix. This is
the blank.
• Add 1 drop of HI 93719D-0 EGTA solution to the second cuvette
(# 2), replace the cap and invert the cuvette several times to
mix. This is the sample.
• Place the blank (# 1) into the holder and close the lid.
• Press ZERO key. The meter will show “-0.0-” when the meter is zeroed and ready for measurement.
• Remove the blank (# 1), insert the sample (# 2) into the instrument,
and close the lid.
• Press READ to start the reading. The instrument displays concentration
in mg/L of magnesium hardness, as CaCO
3
.
10 mL
10 mL
# 1
# 1
# 1
# 2
# 2
# 2
Hardness Mg
MAGNESIUM HARDNESS
SPECIFICATIONS
Range
0.00 to 2.00 mg/L
Resolution
0.01 mg/L
Accuracy
±0.11 mg/L ±5% of reading
Typical EMC
±0.02 mg/L
Deviation
Light Source
Tungsten lamp with narrow band interference filter @ 525 nm
Method
Adaptation of the
Standard Methods for the Examination of Water and Wastewater,
18
th
edition, EDTA colorimetric method. The reaction between magnesium and reagents
causes a reddish-violet tint in the sample.
REQUIRED REAGENTS
Code
Description
Quantity
HI 93719A-0
Mg indicator
0.5 mL
HI 93719B-0
Alkali solution
0.5 mL
HI 93719C-0
EDTA solution
1 drop
HI 93719D-0
EGTA solution
1 drop
REAGENT SETS
HI 93719-01 Reagents for 100 tests
HI 93719-03 Reagents for 300 tests
For other accessories see page 128.
MEASUREMENT PROCEDURE
• Select the
Magnesium Hardness method using the procedure de-
scribed in the
Method Selection section (see page 12).
• Rinse a graduated beaker several times with unreacted sample,
before filling it to the 50 mL mark with the sample.
• Add 0.5 mL of HI 93719A-0 Magnesium indicator solution, then
swirl to mix.
• Add 0.5 mL of HI 93719B-0 Alkali solution and swirl to mix. Use
this solution to rinse 2 cuvettes.