Hanna Instruments HI 38073 User Manual

Instruction Manual

HI 38073

Phosphorus

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:

HI 93713-0 Reagent, packets (100 pcs);

•

• 1 checker disc (containing the 38073 disc);

• 2 glass vials with caps;
1 syringe (1 mL) with tip.

•

Note: Any damaged or defective item must be returned in

its original packing materials.

for

Soil

SPECIFICATIONSSPECIFICATIONS

SPECIFICATIONS

SPECIFICATIONSSPECIFICATIONS

Range 0 to 130 mg/L (ppm) as Phosphorus
Smallest Increment 3.3 mg/L (ppm) Phosphorus
Analysis Method Colorimetric
Sample Size 0.75 mL extract
Number of Tests 100
Case Dimensions 235x175x115 mm (9.2x6.9x4.5")
Shipping Weight 435.5 g (15.4 oz.)

SIGNIFICANCE AND USESIGNIFICANCE AND USE

SIGNIFICANCE AND USE

SIGNIFICANCE AND USESIGNIFICANCE AND USE

Phosphorus belongs to the primary macronutrient group. It is
an essential element to plant growth and is needed in large
amounts. Phosphorus exists in soil mainly as P. It is adsorbed
at the surfaces of iron and aluminum oxides or in association
with calcium. It also occurs in organic forms and may be
released by microbial activity. It is absorbed by roots only in its
maximum oxidation state as the orthophosphoric ion H

2-

HPO

, depending on the pH. Moreover, its absorption is

4

mostly efficient for pH values between 5 and 7: this implies
that acidic or calcareous soil needs to be corrected to neutral pH
values for better tillage yield.

Note:

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

CHEMICAL REACTIONCHEMICAL REACTION

CHEMICAL REACTION

CHEMICAL REACTIONCHEMICAL REACTION

Adaptation of the ascorbic acid method. The reaction be­tween phosphate and the reagent causes a blue tint in the
sample.

INSTRUCTIONSINSTRUCTIONS

INSTRUCTIONS

INSTRUCTIONSINSTRUCTIONS

READ THE ENTIRE INSTRUCTIONS BEFORE USING THE KIT

• Obtain a Mehlich extract from the soil sample by
performing the Mehlich extraction.

• Using the syringe, add to each glass vial 0.75 mL of
sample.

Note: To measure exactly 0.75 mL of sample with the

syringe, push the plunger completely into the syringe
and insert the tip into sample. Pull the plunger out
until the lower edge of the seal is on 0.0 mL mark of
the syringe. Insert the syringe into the vial and push

ISTR38073 09/00 PRINTED IN ITALY

the sample out until the lower edge of the seal is on

2PO4

the 0.75 mL mark (the longer mark between 0.7
and 0.8).

• Add to each glass vial demineralized water up to the

7.5 mL mark, replace caps and swirl to mix.

-

or

• Remove caps and insert one of the vials into the left
hand opening of the checker disc. This is the blank.

• Add to the other
glass vial 1 packet
of HI 93713-0 Re­agent. Replace the
cap and shake vig­orously for 20
seconds. This is the
reacted sample.

• Wait for 3 minutes.

7.5 mL

• Remove the cap and insert
the reacted sample into the
right hand opening of the
checker disc.

• Hold the checker disc so
that a light source illumi­nates the samples from the
back of the windows.

• Keep the checker disc at a distance of 30-40 cm (12­16") to match the color. Rotate the disc while looking at
the color test windows and stop when you find the color
match. Read the value in the result window, multiply
by 3.3 and record it in mg/L (or ppm) of Phosphorus.

For best results: Perform the reading three times and

take the average value (divide by 3 the sum of the
three numbers). Intensely colored samples will make
the color matching difficult and they should be
adequately treated before performing the test. Sus­pended matter in large amounts should be removed
by prior filtration.

Caution: Ultraviolet radiation may cause fading of colors.

When not in use, keep the disc protected from light,
in a cool and dry place.

Interferences: iron above 5 ppm; copper above 10 ppm;

hydrogen sulfide, arsenate and highly buffered
samples.

REFERENCESREFERENCES

REFERENCES

REFERENCESREFERENCES

Standard Methods for the Examination of Water and Waste-

th

water, 18

edition, 1992.

P. Sequi, Chimica del suolo, Patron Editore, Ed. 1991.

HEALTH AND SAFETYHEALTH AND SAFETY

HEALTH AND SAFETY

HEALTH AND SAFETYHEALTH AND SAFETY

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