LaMotte TOTAL HARD NESS TEST KIT PHT-DR-LI - Manual (Page 2)

PRO CE DURE
1. Fill the test tube (0608) to the 12.9 mL line with the water sample.
2. Add five drops of *Hardness Reagent #5 (4483) and mix.
3. Add five drops of *Hardness Reagent #6 Solution (4485) and mix. A
red color will develop.
4. Fill the Direct Reading Titrator (0382) with Hardness Reagent #7
(4487DR) in the manner described in the instruction manual. Insert
the titrator in the center hole of the test tube cap.
5. While gently swirling the tube, slowly press the plunger to titrate the
sample until the red color changes to blue. Read the test result
directly from the scale where the large ring on the Titrator meets the
Titrator barrel. The result is expressed as Total Hardness in ppm
CaCO
3
.
EXAMPLE: Plunger tip is 3 minor divisions below line 80. Test
result is 80 plus (3 divisions x 4) equals 92 ppm.
6. If the plunger tip reaches the bottom line on the titrator scale
(200 ppm) before the endpoint color change occurs, refill the titrator
and continue the titration. When recording the test result, be sure to
include the value of the original amount of reagent dispensed
(200 ppm).
7. Parts per million CaCO
3
test results may be converted to grains per
gallon (gpg) CaCO
3
by means of the following formula:
gpg CaCO
3
= ppm CaCO
3
x 0.058
ANAL Y SIS OF HARD NESS IN SALT WA TER
When sea and estuarine waters containing very high levels of mineral salts
are to be tested, the sample must be diluted to fall within the range of the
test kit. This test set is supplied with a calibrated pipet for performing the
simple, convenient dilution described below.
1.
Use the 0.5 mL pipet (0353) to transfer 0.5 mL of the salt water to be
tested to the test tube (0608).
2. Fill the test tube to the 12.9 mL line with distilled water (1:25.8
dilution).
3. Follow Steps 2 through 6. Multiply the resulting titrator reading by
25.8 to obtain the test result expressed as Total Hardness in ppm
CaCO
3
.
LaMOTTE COM PANY
Helping Peo ple Solve An a lyt i cal Chal lenges ®
PO Box 329 • Chestertown • Mary land • 21620 • USA
800-344-3100 • 410-778-3100 (Out side U.S.A.)
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