DIS SOLVED OX Y GEN TEST KIT
WARNING! This set contains chemicals
that may be harmful if misused. Read
cautions on individual containers
carefully. Not to be used by children
except under adult supervision
CODE 5856
For determining the dissolved oxygen content of water, this test kit uses
the azide modification of the Winkler Method and employs a LaMotte
Direct Reading Titrator in the final titration.
QUANTITY CONTENTS CODE
30 *Manganous Sulfate Solution *4167-G
30 *Alkaline Potassium Iodide Azide *7166-G
30 *Sulfuric Acid, 1:1 *6141WT-G
60 *Sodium Thiosulfate, 0.025N *4169-H
30 Starch Indicator Solution 4170WT-G
1 Direct Reading Titrator, 0 - 10 Range 0377
1 Test Tube, 5-10-12.9-15-20-25 mL,
glass, w/cap
2 Bottles, Water Sampling, 60 mL, glass 0688-DO
1 Graduated Cylinder, 25 mL, plastic 2-2297
*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.
To order individual reagents or test kit components, use the specified code
number.
NOTE: A Check Standard is needed to perform an “EPA Accepted”
test.
0608
DI RECT READ ING TITRATOR IN STRUC TIONS
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
BarrelPlunger Adapter tip
1. Fill the titration tube to the specified line with the water sample.
2. Add the reagents as specified in the instruction for the individual
test method.
3. Cap the tube with the special titration tube cap. Mix by swirling
gently.
4. Depress the plunger of the Titrator.
5. Insert the adapter tip into the spe cial plas tic plug in the ti trat ing
so lu tion bot tle.
6. Invert the bottle. Hold the bottle and
the Titrator firmly together. Slowly pull
out the plunger until the large ring on
the plunger is opposite the zero (0) line
on the scale.
7. If an air bubble appears in the Titrator
barrel or the adapter tip, partially fill the
barrel and pump the titration solution
back into the inverted reagent bottle to
expel the bubble.
NOTE: When filling the Titrator from a container without a
special plug, submerge the adapter tip below the surface of the
solution and pull out the plunger. Remove air bubbles.
8. Turn the bottle right side up and remove the Titrator.
9. Insert the adapter tip into the opening in the titrator tube cap.
Slowly depress the plunger to dispense the titrating solution. Gently
swirl the tube to mix the solution.
10. Continue adding the titrating solution until the specified color
change occurs. If the color change does not occur when the large
ring on the plunger reaches the bottom of the scale, refill the
Titrator to the zero line. Continue the titration until the color
change occurs.
11. Read the test result directly from the scale where the large ring on
theTitrator meets the Titrator barrel. If the Titrator was refilled to
reach the final color change, add the total amounts of titrant used
to determine the final test result.
12. If no ad di tional tests are to be made, dis card the re main ing ti trat ing
so lu tion in the Titrator. Do not re turn the ti trat ing so lu tion to the
re agent bot tle. Thor oughly rinse the ti tra tion tube and the Titrator.
Do not remove the plunger or the adapter tip from the Titrator.
DIS SOLVED OX Y GEN TEST PRO CE DURE
COL LEC TION & TREAT MENT OF THE WA TER SAM PLE
Steps 1 through 4 below describe proper sampling technique in shallow
water. For sample collection at depths beyond arm’s reach, special water
sampling apparatus is required (e.g., the LaMotte Water Sampling
Chamber, Code 1060; Model JT-1 Water Samplers, Code 1077; Water
Sampling Outfit, Code 3103; or Code 3-0026 Water Sampling Bottle).
1. To avoid contamination, thoroughly rinse the Water Sampling
Bottle (0688-DO) with sample water three times.
2. Tightly cap the bottle and submerge to the desired depth. Remove
cap and allow the bottle to fill.
3. Tap the sides of the submerged bottle to dislodge any air bubbles
clinging to the inside. Replace cap while the bottle is still
submerged.
4. Retrieve bottle and examine it carefully to make sure that no air
bubbles are trapped inside. Once a satisfactory sample has been
collected, proceed immediately with Steps 5 & 6 to “fix” the
sample.
NOTE: Be careful not to introduce air into the sample while
adding the reagents in Steps 5 & 6. Simply drop the reagents into
sample. Cap carefully, and mix gently.
5. Add 8 drops of *Manganous Sulfate Solution (4167) and 8 drops of
*Alkaline Potassium Iodide Azide (7166). Cap and mix by
inverting several times. A precipitate will form. Allow the
precipitate to settle below the shoulder of the bottle before
proceeding.
6. Add 8 drops of *Sulfuric Acid, 1:1. Cap and gently shake until the
reagent and the precipitate have dissolved. A clear-yellow to
brown-orange color will develop, depending on the oxygen content
of the sample.
NOTE: Following the completion of Step 6, contact between the water
sample and the atmosphere will not affect the test result. Once the
sample has been “fixed” in this manner, it is not necessary to perform
the actual test procedure immediately. Thus, several samples can be
collected and “fixed” in the field, and then carried back to a testing
station or laboratory where the test procedure is to be performed.
TITRATION
1. Fill the test tube (0608) to the 20 mL line with the “fixed” sample
and cap.
NOTE: For more precise oxygen measurements, fill graduated
cylinder (2-2297) to 20 mL line with sample. Transfer to test tube
(0608). Cap.
2. Fill the Direct Reading Titrator (0377) with *Sodium Thiosulfate,
0.025N (4169).
3. Insert the Titrator into the center hole of the test tube cap. While
gently shaking the tube, slowly press the plunger to titrate until the
yellow-brown color is reduced to a very faint yellow.
NOTE: If the color of the “fixed” sample is already a very faint
yellow, skip to Step 4.
4. Remove the Titrator and cap. Be careful not to disturb the Titrator
plunger, as the titration begun in Step 3 will be continued in Step
5. Add 8 drops of Starch Indicator Solution (4170WT). Sample
should turn blue.
5. Replace the cap and Titrator. Continue titrating until the blue
color just disappears. Read the test result directly from the scale
where the large ring on the Titrator meets the Titrator barrel.
Record as ppm dissolved oxygen.
NOTE: Each minor division on the Titrator scale equals 0.2 ppm.
6. If the plunger tip reaches the bottom line on the Titrator scale
(10 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 (10 ppm).
LaMOTTE COM PANY
Help ing 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.) • Fax 410-778-6394
Visit us on the web at www.lamotte.com
SM
5.11
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