Hanna Instruments hi 3845 ユーザーズマニュアル
Instruction Manual
www.hannainst.com
Dear Customer,
Thank you for choosing a Hanna Product. Please read the
instructions carefully before using the chemical test kit. It
will provide you with the necessary information for correct
use of the kit.
Remove the chemical test kit from the packing material and
examine it carefully to make sure that no damage has
occurred during shipping. If there is any noticeable dam-
age, notify your Dealer or the nearest Hanna office
immediately.
Each kit is supplied with:
Thank you for choosing a Hanna Product. Please read the
instructions carefully before using the chemical test kit. It
will provide you with the necessary information for correct
use of the kit.
Remove the chemical test kit from the packing material and
examine it carefully to make sure that no damage has
occurred during shipping. If there is any noticeable dam-
age, notify your Dealer or the nearest Hanna office
immediately.
Each kit is supplied with:
• HI 3845A-0 Chromium MR-HR Reagent, packets
(100 pcs);
• HI 3845B-0 Chromium MR-HR Reagent , 1 bottle
(17 g);
• HI 3845C-0 Chromium MR-HR Reagent , 2 bottles
with dropper (60 mL);
• Starch Indicator, 1 bottle with dropper (25 mL);
• 1 calibrated plastic vessel (20 mL);
• 1 plastic pipette (1 mL);
• 1 plastic test tube, graduated with cap;
• 1 spoon.
• 1 calibrated plastic vessel (20 mL);
• 1 plastic pipette (1 mL);
• 1 plastic test tube, graduated with cap;
• 1 spoon.
Note: Any damaged or defective item must be returned
in its original packing materials.
HI 3845
Chromium
Medium Range
and High Range
Test Kit
ISTR3845R2 10/02 PRINTED IN ITALY
SIGNIFICANCE AND USE
CHEMICAL REACTION
Chromate is determined by a titrimetric method. Only the
hexavalent chromium will react with iodide in acid solution
(Step 1): the amount of iodine generated is equivalent to
the chromium in the sample. The liberated iodine is then
titrated with standard sodium thiosulfate solution that
reduces the iodine back to iodide ions (Step 2).
hexavalent chromium will react with iodide in acid solution
(Step 1): the amount of iodine generated is equivalent to
the chromium in the sample. The liberated iodine is then
titrated with standard sodium thiosulfate solution that
reduces the iodine back to iodide ions (Step 2).
Step 1: 2CrO
4
2-
+ 16H
+
+ 6I
–
→
→
3I
2
+ 8H
2
O + 2Cr
3+
Step 2: I
2
+ 2S
2
O
3
2–
→
2I
–
+ S
4
O
6
2–
Chromium salts are widely used in industrial processes, such
as metal finishing and plating industries, as well as in the
leather industry as a tanning agent, and in the manufac-
ture of paints, dyes, explosives and ceramics. Chromium
may enter a water supply through the discharge of waste
from these industries and may also be discharged from
chromate-treated cooling waters, where they are frequently
added for corrosion control. The hexavalent state of chro-
mium is toxic to humans, animals and aquatic life. It can
also produce lung tumors when inhaled and readily induces
skin sensitization. The Hanna Chromium Test Kit is portable
and can be used in the field as well as in the laboratory,
being able to determine traces of chromium up to 1000
ppm.
as metal finishing and plating industries, as well as in the
leather industry as a tanning agent, and in the manufac-
ture of paints, dyes, explosives and ceramics. Chromium
may enter a water supply through the discharge of waste
from these industries and may also be discharged from
chromate-treated cooling waters, where they are frequently
added for corrosion control. The hexavalent state of chro-
mium is toxic to humans, animals and aquatic life. It can
also produce lung tumors when inhaled and readily induces
skin sensitization. The Hanna Chromium Test Kit is portable
and can be used in the field as well as in the laboratory,
being able to determine traces of chromium up to 1000
ppm.
Note: mg/L is equivalent to ppm (parts per million).
Range
0 to 100 ppm Cr(VI) MR
100 to 1000 ppm Cr(VI) HR
Smallest Increment
5 ppm Cr(VI) MR
50 ppm Cr(VI) HR
Analysis Method
Drop-Count Iodometric Titration
Sample Size
5 mL MR
0.5 mL
HR
Number of Tests
100 (average)
Case Dimensions
235x175x115 mm (9.2x6.9x4.5")
Shipping Weight
416 g (14.7 oz.)
SPECIFICATIONS
INSTRUCTIONS
READ THE ENTIRE INSTRUCTIONS BEFORE USING THE KIT
• Remove the cap from the plastic vessel. Fill the vessel
• Remove the cap from the plastic vessel. Fill the vessel
with 5 mL of sample using the graduated plastic test
tube for Chromium Medium Range. In case of Chromium
High Range fill the vessel with 0.5 mL of the sample by
means of the 1 mL dropper and add D.I. water up to
the 5 mL mark.
tube for Chromium Medium Range. In case of Chromium
High Range fill the vessel with 0.5 mL of the sample by
means of the 1 mL dropper and add D.I. water up to
the 5 mL mark.
• Add 1 powder packet of HI 3845A-0 reagent and swirl
gently to dissolve it.
• Using the plastic spoon provided, add 1 spoon of HI
3845B-0 reagent and swirl gently to mix.
• Wait for 5 minutes to allow reaction to
occur, leaving the plastic vessel closed
and protected from direct sunlight.
and protected from direct sunlight.
• Begin the drop-count iodometric titration slowly adding
drops of HI 3845C-0 reagent, while swirling the solution
and counting the drops. Continue adding the titration
reagent until the yellow color of the solution is almost
disappeared.
and counting the drops. Continue adding the titration
reagent until the yellow color of the solution is almost
disappeared.
• Add 2 to 3 drops of Starch Indicator and mix by
carefully swirling the plastic vessel in tight circles. The
solution will turn a blue color.
solution will turn a blue color.
• Slowly add more drops of the HI 3845C-0 titration
reagent, while swirling and counting the drops, until it
changes from blue to colorless.
changes from blue to colorless.
• To obtain the concentration in ppm of Chromate ion
CrO
4
2-
multiply the total number of drops of HI 3845C-
0 reagent used from the beginning of titration by 5 or
50 respectively, based on whether Chromium Medium
Range or Chromium High Range is being determined.
50 respectively, based on whether Chromium Medium
Range or Chromium High Range is being determined.
# of DROPS
*
5
= ppm Chromate (MR)
# of DROPS
*
50
= ppm Chromate (HR)
• To convert the concentration in ppm of Cr(VI) multiply
the ppm of chromate by 0.45.
• To convert the concentration in ppm of Na
2
CrO
4
multiply
the ppm of chromate by 1.4.
Note: To measure Chromium in the 0-1.0 ppm range, use
the HI 3846 Chromium Test Kit.
REFERENCES
Vogel's, Textbook of quantitative chemical analysis, 5
th
ed.,
Longman Scientific and Technical
HEALTH AND SAFETY
The chemicals contained in this test kit may be hazardous if
improperly handled. Read Health and Safety Data Sheets
before performing the test.
improperly handled. Read Health and Safety Data Sheets
before performing the test.