Hanna Instruments HI38033 User Manual

Instruction Manual

HI 38033

Total Hardness

0-30 gpg range

Test Kit

www.hannainst.com

Dear Customer,
Thank you for choosing a Hanna Product.
Please read the instruction sheet carefully before using the

test kit. It will provide you with the necessary information for
correct use of the kit. If you need additional information, do
not hesitate to e-mail us at [e-mail].

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 damage,
notify your Dealer or the nearest Hanna office immediately.

Each kit is supplied with:

Buffer Solution pH 10.2±0.2, 1 bottle with dropper

•
(30 mL);

Calmagite Indicator, 1 bottle with dropper (10 mL);

•
HI 38033-0 EDTA Solution, 2 bottles (2x75 mL);

•
1 plastic beaker (20 mL) with cap;

•
1 plastic pipette (1 mL).

•

Note: Any damaged or defective item must be returned in its

original packing materials.

Specifications

Range 0 to 30 gpg CaCO
Smallest Increment 1 gpg CaCO
Analysis Method EDTA titration
Sample Size 10 mL
Number of Tests 100
Case Dimensions 235x175x115 mm (9.2x6.9x4.5")
Shipping Weight 457 g (16.1 oz)

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Significance and use

Water hardness has traditionally been defined as the capacity
of water to precipitate soap. The ionic species in water
causing the precipitation were later found to be primarily
calcium and magnesium. At the present time, water hardness
is a quantitative measure of these ions in the water sample.
Now it is also known that certain other ion species, such as
iron, zinc and manganese, contribute to the overall hardness
of water. The measure and subsequent control of water
hardness is essential to prevent scaling and clogging in water
pipes. The Hanna hardness test kit makes monitoring easy
and quick. The compact size provides the versatility to use the
kit anywhere and the design makes the kit easy to handle.

Note: 1 gpg (grains per gallon) CaCO3 is equivalent to 17

ppm CaCO3 (where ppm - parts per million - is
equivalent to mg/L).

Chemical Reaction

The hardness level as gpg calcium carbonate (CaCO3) is
determined by an EDTA (ethylene-diamine-tetraacetic acid)
titration. The solution is first adjusted to a pH of 10 using a
buffer solution. The indicator chelates with metal ions such as
magnesium or calcium to form a red colored complex. As EDTA
is added, metal ions complex with it. After all the free metal
ions have been complexed, an excess EDTA removes the metal
ions complexed with the indicator to form a blue colored
solution. This color change from red to blue is the endpoint of
the titration.

Instructions

READ ALL THE INSTRUCTIONS BEFORE USING THE TEST KIT

• Remove the cap from the plastic vessel. Rinse the plastic
vessel with the water sample, fill to the 10 mL mark and
replace the cap.

• Add 5 drops of Buffer Solution through the cap port and
mix carefully by swirling the vessel in tight circles.

x 5x 5

x 5

x 5x 5

• Add 1 drop of Calmagite Indicator through the cap port
and mix as described above. The solution becomes a red­violet color.

x 1x 1

x 1

x 1x 1

• Fill the plastic pipette with HI 38033-0 EDTA Solution
and insert the tip into the cap port of the plastic vessel.
Add the solution drop by drop, swirling to mix after
each drop, while keeping an accurate count of the number
of drops being added to the solution in the vessel.

• Continue adding titration solution until the solution in
the plastic vessel becomes purple. Then mix for 15 seconds
after each additional drop until the solution turns blue.

• Record the number of drops needed to obtain the final
color change as gpg CaCO3 of total hardness of your
sample.

drops of titrant = gpg CaCO

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References

Standard Methods for the Examination of Water and
Wastewater, 20

1987 Annual Book of ASTM Standard, vol. 11.01 Water (1).

th

Edition, 1998.

Accessories

HI 38033-100 Replacement kit (100 tests)
HI 740032P cap for 20 ml plastic beaker (10 pcs)
HI 740037P 20 ml plastic beaker (10 pcs)

Safety Data Sheets

The chemicals contained in this kit may be hazardous if
improperly handled. Read the relevant Safety Data Sheet
before performing this test.

ISTR38033R2 02/07