Chemical Test Procedure Final

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PA CK AG ED

DRINKING WATER

TEST FOR COLOUR

PLATINUM COBALT METHOD –VISUAL COMPARITION

S.No Contents Page No.

1 Colour 1

2. Odour 3

3 Taste 4

4 Turbidity, NTU 5

5 Total Dissolved Solids, mg/l, max 7

6 pH 8

7 Barium 9

8 Copper 11

9 Manganese 14

10 Nitrate 17

11 Nitrite 19

12 Iron 22

13 Zinc 24

14 Chloride 27

15 Sulphate 29

16 Alkalinity 31

17 Calcium 33

18 Magnesium 35

19 Residual Free Chlorine 37

20 Sulphide 39

21 Anionic Surface agent 41

22 Aluminium 45

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PRINCIPLE:

Colour is measured by visual comparison of the sample with platinum cobalt

standard

APPARATUS:

1. Nessler cylinder- 50 ml capacity

2. Filter assembly (0.45µm)

3. Centrifuge

CHEMICALS:

1. Potassium chloroplatitious chloride,

2. Cobaltous chloride,

3. Hydrochloric acid

REAGENTS:

Standard Chloro palatinate Solution:

Dissolve 0.1246 potassium chloro palatinate and 0.10 g Cobaltous chloride in

distilled water containing 10 ml of conc. Hydrochloric acid dilute to 100 ml with

distilled water. This standard solution is equivalent to 500 colour units

PREPARATION OF STANDARDS:

Prepare standards color units of 0,2,5,10,20,30 & 40 by using 0.2,0.5,1.0,2.0,3.0

& 4.0 ml standard chloro palatinate solution with distilled water to 50 ml

PROCEDURE:

1. Remove turbidity by using centrifuge (or) filter assembly

2. Collect 50 ml of sample in Nessler tube and compare with the color standards

CALCULATION:

Color Units = 50 x A

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V

A = Estimate color of sample

V = Volume in ml sample take

REPORTS:

Color Units Record to Nearest

1 to 50 151 to 100 5101 to 250 10

TEST FOR ODOUR

APPARATUS:

1. Wide mouth glass stopper bottles-1 lit

2. Hot plate

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CHEMICALS:


2. Activated carbon

Preparation of Apparatus

Rinse the wide- mouth glass- stopped bottles with hydrochloric acid and render

then completely odor less by repeated, washing with odor-free distilled water,

which can be prepared by passing distilled water through a column of granulated

activated carbon

PROCEDURE:

As soon as possible after collection of sample, fill a bottle half-full of sample, insert

the stopper, shake vigorously for 2 to 3 seconds and then quickly observe the odor, the

sample taken for observation of odor shall be at room temperature. When it is desired to

record the odor at an elevated temperature, make the observation after warming the

sample in a stopper bottle to about 60º c

Report:

Report the odor agreeable or disagreeable

TEST FOR TASTE

APPARATUS

1. Glass beaker – 50 ml

2. Water bath

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CHEMICALS:

1. Sodium chloride

Reference sample

Dissolve 2 gms of pure sodium chloride in 1000 ml taste and odor free distilled water

PROCEDURE:

Maintain the sample’s temperature of 15º to 27º C and transfer 50 ml into a 100 ml

Clean beaker. Compare by tasting, the taste of the sample with reference Sample and

report the taste

Report:

Report the taste as agreeable or acceptable if the taste of the water is better than

Reference sample

TEST FOR TURBIDITY

NEPHELOMETRIC METHOD

APPARATUS:

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1. Turbidity meter

2. Filter assembly

CHEMICALS:

1. Hexamethylene tetra mine

2. Hydrazine sulphate

Reagents:

1. Turbidity free water:

Pass distilled water through membrane filter having a pore size not greater than

0.45µm

2. Hexamethylene Tetramine solution:

Dissolve 10.0g Hexamethylene Tetramine in distilled water and dilute to 100 ml.

3. Hydrazine sulphate solution:

Dissolve 1.0g-hydarzine sulphate in distilled water and dilute to 100 ml

4. Turbidity standard suspension 1:400 NTU

In a 100 ml volumetric flask mix 5.0 ml hydrazine sulphate solutions with 5ml

hexamethylene tetramine solution. After 24 hours, dilute to 100 ml with distilled

water and mix well.

5. Turbidity standard suspension:

Dilute 10 ml turbidity standard 1 to 100 ml with distilled water (40 NTU)

PROCEDURE

1. Calibrate the instrument or check the accuracy of instrument with turbidity standards

2. Shake the sample & Pour the sample into turbidity meter tube

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3. Read turbidity directly from instrument scale

Calculation:

Turbidity units = Report the value of Instrument

Report:

Report turbidity as follows

Turbidity Range in units

Record to Nearest

0-1 0.051-10 0.110-40 140-100 5100-400 10

TEST FOR TOTAL DISSOLVED SOLIDS

GRAVIMETRIC METHOD: (FILTERABLE RESIDUE)

APPARATUS:

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1. Filter assembly with 0.45 micron filter paper

2. Drying oven- Maintain the temperature up to 180ºC

3. Desiccator,

4. Analytical balance-0.1 mg Accuracy

5. Evaporating dish-100 ml capacity

PROCEDURE:

Heat the clean evaporating dish to 180ºC for 1 hour. Cool in the desiccators &

weigh accurately

Filter the sample through filter assembly, Pipette out 100 ml of filtered sample to

a weighed evaporating dish on a steam bath & continue evaporation

After completing the evaporation of water, transfer the dish to an oven at 103-

105ºC and dry to constant mass,(usually for 2 hours).

Cool the dish in a desiccators and weigh the dish to the accuracy

Calculation

Filterable Residue, mg/1 = 1000 x M

V

Where

M = Mass in milligram of filterable residue

V = Volume in ml of the sample taken

TEST FOR pH VALUE

ELECTROMETRIC METHOD:

APPARATUS

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1. pH meter

2. Thermometer

3. Magnetic stirrer

CHEMICALS:

1. pH Buffer Tablets 4.0, 7.0 and 9.2

2. Double distilled water.

Buffer solution:

Dissolve each tablet of buffer 4.0, 7.0, 9.2 pH respectively in freshly collected double

water and make into 100 ml in a standard flask

Procedure:

Calibrate the pH meter with known buffer solution

Immerse the electrode into the sample & measure the pH.

Note the pH and temperature value & record

If there is a drift in reading, take a second reading with fresh aliquot of sample

and report it

Calculation:

Report pH to the nearest 0.01 units

TEST FOR BARIUM

VOLUMETRIC METHOD:

APPARATUS:

1. Hot Plate,

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2. Filter Assembly

3. Magnetic Stirrer

CHEMICALS:

1. Ammonium Dichromate AR

2. Ammonium acetate

3. Ammonium Hydroxide

4. Potassium iodide

5. Sodium Thio Sulphate


7. Ammonium chloride

Reagents:

Ammonium dichromate solution 10 % Dissolve 50 g of ammonium dichromate in

water and dilute to 500 ml

Ammonium acetate solution 30 %: Dissolve 150g of Ammonium acetate in water,

neutralize with ammonium hydroxide and dilute to 500 ml

Dilute Ammonium acetate wash solution: Dilute 20 ml of the ammonium acetate

solution to 1000 ml

Potassium iodide solution (10%) v/v: Dissolve 25 g in 250 ml distilled water

Sodium thio sulphate (0.1 N):

Dissolve 12.5 g of sodium thio sulphate in water and dilute to 500 ml and add few

drops of chloroform

Standardize this solution against 0.1 N potassium dichromate using starch as

indicator

Hydrochloric acid(1:1): Dilute 50 ml of conc. hydrochloric acid to 50ml of

distilled water

PROCEDURE:

1. Acidify about 5 lit Liter Portion (at least 2 lit) of sample with 5 ml dilutes

hydrochloric acid and concentrate to about 200 ml

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2. Add about 0.5 g of Ammonium chloride and precipitate iron and Aluminum with

5 ml Ammonium hydroxide.

3. Boil & filter and wash. To filtrate add excess (10 ml ) ammonium acetate 30 %

solution keeping total volume about 200 ml

4. Heat to boiling and add with stirring about 5 ml ammonium dichromate solution.

5. Cool slowly and wash the precipitates free of chromate with dilute ammonium

acetate wash solution by decantation and filtration.

6. Dissolve the precipitate in about 10 ml hydro chloric acid (1:1 v/v) and hot water

7. Wash the filter and dilute the solution to about 400 ml add about 50 ml freshly

prepared 10% potassium iodide solution

8. Dissolve the precipitate in about 10 ml hydrochloric acid (1:1 v/v) and hot water

9. Wash the filter and dilute the solution to about 400 ml and add about 50 ml

freshly prepared 10% potassium iodide solution

10. Mix Carefully and titrate liberated iodine(12) filter 3 to 4 minutes with 0.1 N

sodium thio sulphate

Calculation:

1 ml of 0.1 N sodium thiosulphate. (Na2S203) = 4.578 mg barium (Ba)

TEST FOR COPPER

NEOCUPROINE METHOD:

APPARATUS:

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Spectrophotometer (457 nm)

Hot plate

Separating funnel – 125 ml capacity

Glass wares

CHEMICALS:

Ammonium hydroxide

Chloroform

Hydrochloric acid

Hydroxylamine hydrochloride

Iso propyl alcohol

Neocuproine

Nitric acid,

Sulphuric acid

Sodium citrate,

Copper metal powder AR

Hydrogen peroxide.30%

Reagents:

Hydroxylamine Hydrochloride solution 20%

Dissolve 20 gm of hydroxylamine hydrochloride in 100 ml of water.

Neocuprine solution 0.1%

Dissolve 0.1 g of Neocuproine in 50 ml of isopropyl alcohol. Dilute to 100

ml with double distilled water

Sodium Citrate solution 25%

Dissolve 25 g of hydrate sodium citrate in water and make up to 100

ml.Add 1 ml each of Neocuproine solution and hydroxylamine solution.

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Stock copper (ll) solution:

Dissolve 0.2 g of pure copper metal by warming with 6 ml of 1:1 nitric

acid. Add 1 ml of conc. Sulphuric acid and evaporate the solution to dryness.

Dilute the solution to 1 lit with distilled water. (1ml =200 µg of copper (ll).)

Intermediate copper (ll) solution:

Dilute 10 ml of stock solution to 100 ml with distilled water (1 ml =20µg)

Standard copper (ll) solution:

Dilute 1ml of intermediate stock solution to 50 ml with distilled water.

(1 ml =0.4µg)

PROCEDURE:

Boil and cool the 50 ml of acidified (few drops of HCL) sample into 125 ml

separating

Add 5 ml hydroxylamine hydrochloride,10 ml of sodium citrate and 10 ml of

Neocuproine solution, shake well

Add 20 ml of chloroform and shake for 1 minute and allow the layers to

separate and collect the chloroform layer in a dry flask

Repeat shaking with another 20 ml chloroform and collect the chloroform in

the same flask, dilute the volume to 50 ml with isopropyl alcohol

Prepare a reagent blank by treating 50 ml of double distilled water as described

above and measure the optical density of the sample solution at 457nm against

the reagent blank. A Suitable serious of standards are prepared by adding the

following volumes of 0.0,5.0,10.0,15.0,20.0,25.0 ml standard copper (ll)

solution solutions and diluting to 50 ml with water corresponding standards

respectively to 0,0.04,0.08,0.12,0.16 & 0.20 mg/lit of copper

Plot absorbance vs copper concentration (mg/1) for the standards to get a

calibration graph

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Calculation:

=M/sample

M =mg/lit of copper sample directly from the calibration graph

TEST FOR MANGANESE

COLOUER COMPARISON METHOD:

APPARATUS:

Hot plate

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Distillation Apparatus

SO2 Generator or sulphur di oxide solution

Nessler Tubes – 50 ml capacity

CHEMICALS:

Sulphuric Acid

Hydrogen peroxide

Nitric Acid

Potassium permanganate AR

Phosphoric Acid

Potassium per lodate

REAGENTS:

1. Dilute sulphuric acid (1.1) v/v:

Dilute 100ml of conc.sulphuric acid in to 100 ml of distilled water, stir and

cool.

2. Hydrogen Peroxide – Nitric acid mixture:

Mix 50 ml of hydrogen peroxide solution with 50 ml of conc. Nitric acid and

cool.

3. Standard management solutions:

Measure 45.5 ml of 0.1 N potassium permanganate solution in to a 250 ml

beaker add a few drops of dilute sulphuric acid; heat to boiling and then add a

saturated solution of sulphur di oxide in water drop by drop until the

permanganate is just decolorized.

Boil for 15 minute, cool, transfer the solution to a 500 ml graduated flask,

dilute to the mark and mix well (1 ml=0.1 mg of Mn)

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Measure 50 ml of the solution in to a 500 ml graduated flask, add 5ml of

dilute sulphuric acid dilute to the mark and mix well. (1ml=0.01 mg of Mn)

PROCEDURE:

1. Take suitable volume (50ml) of the clear sample in to a 300 ml conical flask

(borosil), add 4ml of dilute sulphuric acid and evaporate to fuming

2. While heating, add few drops of hydrogen peroxide-nitric acid mixture carefully,

until all traces of organic matter destroyed.

3. Cool, add 10 ml of stabilized distilled water and evaporate to fuming again cool.

4. Add 50 ml of stabilized distilled water.2 ml of the phosphoric acid and 0.2 g of

potassium per iodate.bring to the boil and keep just below the boiling point for

one hour

5. Cool, transfer the solution to a nessler tube adjusts the volume to 50 ml with

stabilized distilled water and mix well.

Into five 300 ml conical flasks, Measure 0.0,0.5,1.0,105,2.0 ml of standard

manganese solution (1ml =0.01 mg of Mn) diluting to 50 ml with water

corresponding standards respectively to 0.1,0.2,0.3,0.4 mg/lit of Mn.Treat the

standard as per above procedure.

6. Transfer the solution to nessler tubes dilutes to the mark with distilled water and

mix. Compare the colours of sample and standard

CALCULATIONS:

Manganese (as Mn) mg/1 = w/v

Where W =Amount in mg/lit of manganese present in the standard which matches

the colours obtained with the sample

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V = Volume in ml of the sample taken for the test

TEST FOR NITRATE

CHROMOTROPIC ACID METHOD

PRINCIPLE:

Two moles of nitrate nitrogen react with one mole of chromotropic acid to form a

yellow reaction product having maximum abs at 410 nm

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APPARATUS:

Spectrophotometer

Std flasks – 10 ml capacity

Ice bath

CHEMICALS:

Potassium nitrate AR

Chloroform,

Urea

Sodium sulphate – anhydrous

Antimony metal

Sulphuric acid.

Chromotropic.

REAGENTS:

1. Stock Nitrate solution:

Dissolve 0.7218 g of dry Potassium nitrate in Nitrate free water and dilute to

1000ml.Add 2 ml chloroform ad preservative.

2. Standard Nitrate solution:

Dilute 50 ml stock nitrate solution to 500 ml with Nitrate free water,

(1ml=10µg Nitrate nitrogen

3. Sulphite –urea reagent:

Dissolve 1.25g of urea and 1g of anhydrous sodium sulphite in water and

dilute to 250 ml

4. Antimony reagent:

Dissolve 0.5g Antimony metal by heating in 80ml conc.sulphuric acid. Cool

and add to 200 ml of ice-cold water, warm gently

5. Chromotropic acid reagent:

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Dissolve 100 mg of purified chromotropic acid crystals in 100 ml

conc.sulphuric acid and store in brown bottle

PROCEDURE:

1. Prepare nitrate standard in the range of 1.0 to 5.0mg/1 by diluting 10,20,30,40 &

50 mlof standard nitrate solution to 100 ml with water

2. Pipettes 2.0 ml portions of the standard nitrate solutions, samples and blank in to

dry 10 ml volumetric flasks. To each flask add 1 drop of sulphite-urea reagent

3. Place flasks in tray of cold water(10 to 20ºC) and 2 ml of antimony swirl the

flasks during addition of each reagent and allow the flasks in water tray for

minutes

4. Add 1 ml of chromotropic acid reagent swirl and let stand in cooling bath for 3

minutes

5. Add conc.sulphuric acid to bring volume near the 10 ml mark

6. Stopper the flasks and mix by inverting each flasks four times let it stand for 45

minutes at room temperature and adjust volume to ml with conc.sulphuric acid

7. Perform final mixing very carefully and gently. Read absorbance at 410nm after

15 minutes

CALCULATION:

Nitrate nitrogen (as nitrate) mg/1 = µg of nitrate nitrogen in 10 ml final volume

Volume in ml of sample taken for test

TEST FOR NITRITE

SPECTROPHOTOMETRIC METHOD:

APPARATUS:

Spectro photometer (540 nm)

Nesslers tube – 50 ml capacity

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CHEMICALS:

Potassium dichromate

Calcium hydroxide

Sulphanilamide

Hydrochloric acid

NED di hydro chloride

Sodium oxalate AR

Ferrous ammonium sulphate AR

Sodium nitrate AR

Chloroform

REAGENTS:

1. Sulphanilamide reagent:

Dissolve 5g of the materials in a mixture of 50 ml conc. hydrochloric acid and

300 ml of water; dilute top 500ml with water

2. NED dihydrochloride:

Dissolve 500 mg of the material in 500 ml of water, store in colored bottle in

dark

3. Hydrochloric acid (1.3) v/v:

Add 100 ml of conc. hydrochloric acid in to 300 ml Distilled water.

4. Sodium oxalate:

Dissolve 0.335g of sodium oxalate in 100 ml distilled water.

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5. Ferrous ammonium sulphate (0.05N):

Dissolve 9.803g of ferrous ammonium, sulphate in 10ml of conc.sulphuric

acid and water and dilute to 500 ml.Standardize with standard dichromate

6. Stock nitrate solution:

Dissolve 0.616g of sodium nitrate in water and dilute to 500ml (1 ml=250µg

of nitrite) Preserve with 1 ml of chloroform. Standardize using Sodium oxalate

solution

7. Intermediate nitrate solution:

Dilute 50 ml stock nitrate solution to 250ml with water (1ml=50µg nitrate)

8. Standard Nitrate solution:

Dilute 5 ml of intermediate nitrate solution to 500 ml with water (1ml =0.5µg

nitrate)

PROCEDURE:

1. Take 50 ml of clear sample neutralized to Ph 7, add 1 ml of sulphailamine

solution mix and wait for 8 minutes.

2. Add 1.0 ml of NED dihydrochloride solution and mix immediately, wait for 10

minutes(formation of full color).Measure absorbance at 543 nm.Run parallel

checks frequently against nitrate standards

3. A suitable series of color standards for nitrate nitrogen are prepared by adding the

following volumes of 1.0, 2.0, 3.0, 4.0 & 5.0 ml standard nitrate (1 ml =0.5µg)

solutions and diluting to 50 ml with water. Corresponding standards respectively

to 0.01,0.02,0.03,0.04,0.05 mg of nitrate per liter.

4. Develop colour and compare samples to visual standards

5. Select the concentration where the sample tube color matches the standard tube

color.

Calculation:

Nitrate nitrogen (as NO2) mg/1 = µg NO2

ml of sample

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TEST FOR IRON

COLORIMETRIC METHOD:

APPARATUS:

Hot plate

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Spectrophotometer – 535 nm

Platinum dish. – 25ml capacity

Muffle furnace

CHEMICALS:

1. Potassium hydrogen sulphate

2. Ammonium hydroxide


4. Thio glycolic acid

5. Ferrous ammonium sulphate AR

6. Sulphuric acid

7. Potassium permanganate

REAGENTS:

Dilute hydrochloric acid (1:3) v/v:

Dilute 50 ml of conc. Hydrochloric acid with 150 ml of distilled water stir

and cool.

Thio glycolic acid reagent (10%):

Dilute 10 ml of thio glycolic acid to 100 ml with distilled water and

preserve it in amber colored bottle.

Standard iron solution:

Dissolve 0.702 g of ferrous ammonium sulphate in 100 ml of distilled

water and 10 ml of distilled water and 10 ml of conc. Sulphuric acid. Warm the

solution and add N/8 Potassium Permanganate solution (0.3950g KMNO4 to 100

ml) until the ferrous iron is oxidized as shows by the persistence of slight pink

color.

Dilute to 100 ml (1 ml= 0.1 mg of Fe) Dilute 25 ml of the above solution to 250

ml to get the working standard solution of iron. 1ml=0.01 mg of iron (as Fe).

PROCEDURE:

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1. Evaporate 50 ml of sample to dryness in a platinum dish and ignite gently

and fuse with potassium bisulphate and cool.

2. Dissolve the fused mass in 25ml-distilled water and precipitate iron and

aluminum by adding 5 ml ammonium hydroxide.

3. Filter, dissolve the precipitate in 5 ml of 1:3 hydrochloric acid, dilute the

solution to about 30 ml with distilled water and add 2 ml of thio glycolic

reagent followed by 2.5 ml of ammonium hydroxide.

4. Transfer quantitatively to a Nessler tube and make up to 50 ml. Compare

in Nessler tubes with the color obtained with standard iron solution or

measure the absorbance of the sample solution at 535 nm against the

reagent.

Calibration of standard curve:

A suitable series of standards are prepared by adding the following volumes of

1.0, 2.0, 3.0, 4.0 & 5.0 ml standard iron solution (1.0 ml = 0.01 mg of iron)

diluting to 50 ml with water corresponding standards respectively to 0.2, 0.4,

0.6, 0.8, 1.0mg / lit of Iron. Treat the standard as per above procedure.

Calculation: = M / Volume of sample

M= mg/ lit of iron sample directly from the calibration graph.

TEST FOR ZINC

ZINCON METHOD:

APPARATUS:

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1. Spectrometer (620 nm)

2. Lab glass wares.

CHEMICALS:

Sodium Hydroxide

Potassium Cyanide.

Cyclohexanone

Zincon

Methanol

Potassium Chloride

Boric acid AR

Hydrochloric acid

Zincon Sulphate AR

Reagents:

Sodium hydroxide solution (40 g/1):

Dissolve 20 g of sodium hydroxide to make up to 100 ml with water.

Sodium hydroxide solution (240 g/1):

Dissolve 24 g of sodium hydroxide to make up to 100 ml with water

Potassium cyanide solution:

Dissolve 1 g of Potassium cyanide in 50 ml of water and dilute to 100 ml

Cyclohexanone solution:

Dissolve 10 g of cyclohexanone in 100ml water

Zincon solution:

Dissolve 0.325 g of zincon reagent in 100 ml of methanol by heating

gently, cool dilute to 250 ml std flask (store in brown bottle).

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Borate buffer solution:

Dilute 22 ml of sodium hydroxide solution to 50 ml with water and

dissolve 3.75 of potassium chloride and 3g of boric acid and make up to 100 ml in

a std flask.

Zinc (11) solution:

Dissolve 0.2745 g zinc sulphate in 200 ml of water and dilute to 1 lit (1

ml = 0.1 mg of Zn).

PROCEDURE:

1. Add 1 ml of conc hydrochloric acid to 50 ml of sample and boil for 5

minutes. Cool the solution and adjust the Ph to 7 with sodium hydroxide

solution and make up to 50 ml in a std flask

2. Take 10 ml of this solution 5 g sodium Ascorbate add 1 ml of cyanide

solution,5 ml of buffer solution,3 ml zincon solution and 1 ml

cyclohexanone solution. Make up the solution to 500 ml

3. Prepare a reagent blank by treating 50 ml of double distilled water in the

same way as described above

4. Measure the optical density of the sample solution at 620 nm against the

reagent blank.

5. Calibration: Treat 50 ml portion of standard solution containing

0.02,0.05,0.1,0.5,1.0 & 5.0mg/1 of zinc treat as above and measure the

absorbance

6. Plot absorbance versus milligram of zinc for the standards to get a

calibration graph

7. Read the concentration of zinc in the sample from the calibration graph

Calculation:

Zinc mg/1 = m/v x 1000 Where m = mass of zinc present in mg in the sample

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V = volume of sample in ml

TEST FOR CHLORIDE

ARGENTOMETRIC METHOD:

APPARATUS:

Burette – 50 ml

Erlenmeyer flask -250 ml capacity

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Magnetic stirrer

CHEMICALS:

Potassium chromate

Silver nitrate AR grade

Sodium chloride

Reagents:

1. Standard sodium chloride 0.0141 N : Dissolve 0.824g of Nacl in distilled water and make up to 1000ml

2. Potassium chromate indicator: Dissolve 5g of potassium chromate in 100 ml distilled water.

3. Standard silver nitrate solution 0.0141 N: Dissolve 2.395g of silver nitrate in distilled water and make up to 1000 ml.

PROCEDURE:

1. Take 100 ml sample adjust the Ph to 7.0, 10.0 with H2So4 or NaOH.

2. Add 1 ml of potassium chromate indicator and titrate and against standard silver nitrate solution. To a pinkish yellow end point & Run a blank.

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Calculation:

Chlorides (as Cl) mg/1 = (V1-V2) X N X 35450 --------------------------- = (V1-V2) X 4.998 V3

V1 =Volume in ml of silver nitrate used by the sample

V2 = Volume in ml silver nitrate used by the blank

V3 = Volume in ml by sample taken

N = Normality of silver nitrate

TEST FOR SULPHATE

TURBIDITY METHOD:

APPARATUS:

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Spectrophotometer

Glass wares

CHEMICALS: Barium chloride

Glycerol,

Hydrochloric acid

Ethyl or isopropyl alcohol

Sodium chloride

Sodium sulphate anhydrous

Reagents: Conditioning reagent:

Mix 50 ml glycerol with a solution contain 30 ml conc. hydrochloric acid,300 ml distilled water 100 ml 95% ethyl or isopropyl alcohol and 75 g sodium chloride.

Stock sulphate solution (100 mg/1): Dissolve 0.1479g of anhydrous sodium sulphate in distilled water and dilute to

1000 ml

Hydrochloric acid (1:9 v/v): Add 10 ml conc. hydrochloric acid into 90 ml of distilled water. Cool

PROCEDURE:

1. Take 20 ml clear water sample in 100 ml std flask

2. Add 1 ml 1:9 hydrochloric acid and 1 ml conditioning agent and about 0.5gm of barium chloride mix well for 30 seconds

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3. Read the absorbance on spectrophotometer after 10 minutes at 420 nm.Calibration curve: Prepare a serious of standards and blank (0.0, 5.0, 10.0, 15.0 and 20.0ml of stock sulphate solution, and follow the above procedure. This is 0.0,10.0,20.0,30.0 and 40.0 mg/1 of sulphate)

4. Prepare a calibration curve of standards mg/1 Vs absorbance

Calculation: Sulphate as So4 mg/lit = M ----------------------- Volume of sample

M = mg/lit of Sulphate sample directly from the calibration graph

TEST FOR ALKALINITY

POTENTIOMETRIC METHOD:

APPARATUS: pH meter

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Burette – 50 ml capacity

Magnetic stirrer

CHEMICALS: Distilled water

Conc.Sulphuric acid AR

Phenolphthalein

Methyl red

Bromocresol green indicators

Sodium carbonate

Reagents: Standard 0.02N H2SO4:

Dilute 0.6 ml conc. Sulphuric acid (sp.gr.1.84) to 1000ml.With distilled water; this can be standardized by titrating with 0.02 N sodium carbonate using methyl red as indicator

Phenolphthalein indicator: Dissolve 0.5 g of Phenolpthalein in 100ml of 1:1 (v/v) alcohol/water mixture.

Mixed Indicator solution: Dissolve 0.02 methyl red and 0.01 g bromocresol green in 100 ml

95% ethyl or isopropyl alcohol

0.02N Na2Co3 solution: Dilute 1.0599g of Na2Co3 to 1000 ml with distilled water

PROCEDURE:

Pipette out 50 ml of the sample, add 2 to 3 drops of phenolphthalein indicator,( if there is no pink color, phenolphthalein alkalinity is absent)

Titrate the pink color solution against 0.02N Sulphuric acid taken in the burette to the colorless end point(A).

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To the titrated solution containing Phenolpthalein indicator, add 2 to 3 drops of mixed indicator.

Titrate with standard 0.02N sulphuric acid to light pink color(B)

Calculations:

Phenolpthalein alkalinity (as mg/1 of CaCo3) = A X 0.02 X50 ------------------- X 1000 = A X 20 50

Total alkalinity (as mg/1 of CaCo3) = (A+B) X 0.02 X 50 ------------------------- X 1000 = (A+B) X 20 50

TEST FOR CALCIUM

E.D.T.A TITRIMETRIC METHOD:

Apparatus:

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Hot plate

Lab glass wares

Chemicals:

Murexide or Patton and Reeder’s indicator

Sodium Chloride

Eriochrome black – T


Methanol

Hydrochloric acid

Nitric acid

Sodium hydroxide

EDTA di Sodium salt

Zinc

Reagents:

1. Murexide indicator:

Mix 0.20g of the murexide in 100g of NaCl.

2. P & R indicator:

Mix 1g of P&R indicator with 100 gms of sodium / potassium

chloride.

3. Buffer Solution:

Dissolve 20 gms of sodium hydroxide in distilled water and dilute the

volume to 500ml.

4. 0.01M E.D.T.A (0.02N EDTA):

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Dissolve 3.75gms of E.D.T.A di sodium salt in water and make up to

1000ml in a std flask. This solution is standardize against 0.02N Zinc

solution using EBT – indicator.

5. Zinc 0.02N solution:

Dissolve 0.6538gms Zinc dust in 20ml 1:1 HCl, warm & cool and

make up to 1000ml.

6. Standardization of 0.02N EDTA solution:

Pipette out 20ml Zinc solution Add 5ml of Ammonia buffer solution.

Add 3 to 4 drops of EBT – T indicator solution. Titrate against 0.02N

EDTA solution till the colour changes to blue.

Procedure:

Pipette out 50ml sample into a clean 250 ml conical flask, add about 2ml

of sodium hydroxide solution to produce a pH of 12 to 13 stir.

Add 0.1g of murexide indicator to produce a wine red colour, titrate

against 0.02N EDTA taken in a burette to pure Blue.

Note down the volume of 0.02N EDTA solution (V1) from the burette.

Calculation:

Calcium (as mg/l of CaCO3) = V1x0.02x50x1000 / Sample = V1x20

Calcium (as mg/l of calcium) = V1x0.02x50x1000 / Sample = V1x8

TEST FOR MAGNESIUM

EDTA TITRIMETRIC METHOD:

APPARATUS:

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1. Hot Plate

2. Lab glass wares

Chemicals:

Ammonium chloride

Ammonia solution


Potassium cyanide

Triethanolamine

EDTA disodium salt

Zinc

Hydro chloric acid

Phenol

Reagents:

Erichrome black-T Indicator:

Dissolve 0.5g of EBT and approximately 4.5g of hydroxylamine hydrochloride in

100ml of rectified spirit.

Ammonia – ammonium chloride buffer solution dissolve:

35g ammonium chloride and 285ml of 30% ammonia solution in water and make

up to 500ml

Hydroxylamine hydrochloride (10%) :

Dissolve 10g of hydroxylamine chloride in 100ml of distilled water

Potassium cyanide solution:

Dissolve 10g of potassium cyanide in 100ml of distilled water

Tri ethanolamine solution (10%):

Dissolve 10g of T.E.A in 100ml of distilled water

0.01 method (0.02N EDTA solution:

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Dissolve 1.875g of EDTA di sodium salt in water and make up to 500ml in a

standard flask.

To standardized this solution against 0.02N Zinc solution using EBT as indicator

with ammonia-ammonium chloride buffer solution.

Procedure:

Pipette out 50ml of sample into a clean 250ml conical flask.

Add 10ml of hydroxylamine hydrochloride solution, 2ml of potassium cyanide

solution and 25ml of Tri ethanolamine solution.

Dilute the volume to 150ml using distilled water. Add 5ml of ammonia-

ammonium chloride buffer to bring the pH to 10+ 0.1.

Add 3ml to 4 drops of EBT-Indicator solution.if turns red. Titrate the red color

solution against 0.02N EDTA solution till the colour changes to blue and take the

reading(V2).

Calculation:

Total Hardness = V2 x 0.02 x 50 x 100 = V2 x 20

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TEST FOR RESIDUAL FREE CHLORINE

IODOMETRIC METHOD:

Apparatus:

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1. Lab Class wares

2. Magnetic stirrer,

Chemicals:

1. Potassium Iodide – crystal

2. Sodium thiosulphate

3. Potassium dichromate

4. Starch

5. Acetic acid glacial

Reagents:

Standard potassium dichromate (0.01N):

Standard Sodium Thiosulphate (0.1N)

Dissolve 12.5gms of sodium thio sulphate crystals in distilled water and dilute the

volume to 500ml in a std flask. This is 0.1N strength and adds few crystals of 0.1 to 0.2

gms of sodium carbonate as preservative.

Standard Sodium thio sulphate 0.01N:

Dilute 10ml of above solution to 100ml. Standardize with 0.01N potassium

dichromate solution using starch indicator.

Starch Indicator Solution:

Add 0.5g starch to 80ml boiling distilled and stir well. Dilute to 100ml and boil

few minutes and let us settle over night. Use the clear supernatant.

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Procedure:

Take appropriate volume of the sample (500ml) and add acetic acid to Bring

down the pH to 3 to 4 in the flask.

Add about 1 gm of potassium iodide crystals and mix well.

Add 1 ml of freshly prepared starch solution to the flask.

If there is no blue color, the residual chlorine is absent or below detectable limit.

If blue color is produced, titrate the contents of the flask against 0.01N Sodium

thiosulphate to colorless end point.

Calculation:

Residual Chlorine mg/l (as chlorine) = V2 x 0.01 x 35450

V1

Where

V1 = Volume of the Sample Taken

V2 = Volume of the std Sodium thiosulphate solution.

TEST FOR SULPHIDE

METHYLENE BLUE METHOD:

Apparatus:

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1. Spectro photometer,

2. Droppers,

3. Test tubes

Chemicals:

1. N, N-Dimethyl-p-phenylenediamine-oxalate

2. Sulphuric acid

3. Ferric Chloride

4. Diammonium hydrogen phosphate

5. Methylene blue

Reagents:

Amine sulphuric acid stock solution:

Dissolve 2.7g N, N-Dimethyl-p-phenylenediamine-oxalate in a cold

mixture of 5ml of Conc. Sulphuric acid and 2ml of distilled water-cool and dilute

to 10ml with distilled water. Store in a dark glass bottle.

Amine-Sulphuric acid reagent solution:

Dilute 2.5ml of Stock solution with 97.5ml 1:1 sulphuric acid, store in a

dark glass bottle.

Ferric chloride solution:

Dissolve 125g diammonium hydrogen in 250ml of distilled water

Methylene Blue solution I:

Dissolve 1g of dye (84%) in distilled water and make unto 1 Litre. 0.05ml

(1 drop) is equivalent to 1mg of sulphide per litre.

Methylene Blue solution II:

Dilute 10ml of adjusted methylene blue solution 1 to 100ml.

Procedure:

Transfer 7.5ml of sample to each of two matched test tubes A and B

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Add to tube A 0.5ml of amine-sulphuric acid reagent and 0.15ml of ferric chloride

solution, mix immediately by inverting slowly, only once.

The presence of sulphide will be indicated for the appearance of blue color in use

A

The tubes B add 0.5ml of 1:1 sulphuric acid and 0.15ml of ferric chloride solution

and mix. Color development is generally complete in about 1 minute.

Wait for 3 to 5 minutes and add 1:6 ml of diammonium hydrogen sulphate

solution to tube A & B

Wait for 3 to 15 minutes and make color comparison.

Color Determination: (Visual color estimation)

Add Methylene blue solution I or II, depending on sulphide concentration and and

desired accuracy, drop wise, to the B tube, until color matches that developed in

the A tube.

If we use methylene blue solution I – 0.05ml (1 drop) = 1mg/lit of sulphide when

7.5ml of sample are used.

If we use methylene blue solution II – 0.05ml (1 drop) = 0.1mg/lit of sulphide

when 7.5ml of sample are used.

Calculation:

Sulphide (mg/l) = No of drops of solution I + 0.1 (No of drops of solution II)

TEST FOR ANIONIC SURFACE ACTIVE AGENT

SPECTROPHOTOMETRIC METHOD:

Apparatus:

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Gas Stripping Apparatus – 1 lit Capacity

Filter assembly lab

Glass wares

Chemicals:

Sodium chloride

Ethyl acetate

Chloroform

Ethanol

Methanolsulphuric acid

Phenolphthalein indicator

NaHco3

Na2 Co3

Reagents:

1. Sulphuric acid solution:

0.5 ml / l

2. Ethonolic sodium hydroxide 0.1 mol / lit:

Dissolve 4g of sodium hydroxide pellets in ethanol and dilute to 1000 ml

with the same ethanol.

3. Methylene blue (neutral solution):

Dissolve 0.175 g of methylene blue in water and dilute to 500ml. prepare

the solution at least 24 hours before use.

4. Methylene blue (acidic solution):

Dissolve 0.175 g of methylene blue in 250 ml water and add 3.25 ml of

Sulphuric acid. Dilute with water to 500 ml after mixing prepare the solution

atleast 24 hours before use.

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5. Buffer solution (pH 10):

Dissolve 12 g of sodium hydrogen carbonate and 13.5 g of anhydrous

sodium carbonate in water and dilute to 500 ml.

6. Phenolphthalein solution:

Dissolve 1.0 g of phenolphthalein in 50 ml of ethanol and add 50 ml of

water filter off any precipitate.

7. Dodecyl benzene sulphonic acid methyl ester:

Weigh to the nearest 0.1 mg, 200 mg to 225 mg of dodecyl benzene

sulphonic acid methyl ester in to a round bottomed flask, and add 25 ml of ethanol

– sodium hydroxide solution and some anti-bumping granules. Reflux and boil for

1 hour, after cooling neutralize the solution with sulphuric acid against

phenolphthalein, until it becomes colorless. Transfer the solution to a 500 ml

volumetric flask. Dilute to the mark with water and mix.

Procedure:

Separation of the surfactant:

1.Place a measured quantity of the test sample with 100 g of sodium chloride up to

1000 ml in the gas – stripping apparatus.

2. Add water to bring the sample surface up to the level of the upper stopcock, add

100 ml ethyl acetate.

3. Fill the wash bottle in the gas line (nitrogen or air) two – third full with ethyl

acetate.

4. Pass gas stream of 20 l / h to 50 l / h through the gas – stripping apparatus and

adjust the gas flow.

5. Stop the gas flow after 5 minutes, if a loss of more than 20% of the organic phase

has occurred, discard the test sample.

6. Run off the organic phase completely in to a separating funnel, return any water in

the separating funnel to the gas – stripping apparatus.

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7. Filter the ethyl acetate solution through a dry qualitative gas – filter paper in to a

250 ml flask.

8. Add a further 100 ml of ethyl acetate to the gas stripping apparatus and again pass

nitrogen or air through it for 5 min.

9. Separate the organic layer as described above, using the same separating funnel,

filter and add it to the first portion.

10. Rinse the filter paper and funnel with 25 ml of ethyl acetate.

11. Remove all the ethyl acetate solution on a water both under a hood.

12. Dissolve the residue in about 5 ml of methanol and 50 ml of water.

13. Transfer the solution quantitatively to a 100 ml volumetric flask and dilute to the

mark with water.

Blank Test:

Carry out a blank test at 650 nm and subtract the interpolated absorbance (Ao),

from the absorbency (At) of the test sample.

Test with the Sample:

Transfer a measured volume of the test sample into a separating funnel. This test

portion contains 20 µg to 200 µg of methyline blue active substances.

Add 5 ml of neutral methyline blue solution , 10 ml of buffer solution and 15 ml

chloroform.

Shake evenly and gently about twice a second for a min, preferably in a horizontal

plane.

Allow the layers to separate as completely as possible and swirl the funnel to dislodge

droplets from the side of funnel.

Allow settling for 2 min, then, running as much as possible of the chloroform layer

into a second separating funnel, containing 110 ml of water and 5 ml of acidic

methyl blue solution, shake uniformly but not too vigorously for 1 min as

previously described.

Filter the chloroform layer through a cotton or glass wool filter wetted with

chloroform into a 5 ml volumetric flask.

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Repeat the extraction of the alkaline and acidic solution using a 10 ml portion of

chloroform for the extraction, separate the chloroform layer and filter it, through

the same filter, into volumetric flask.

Repeat the extraction using a further 10 ml portion of chloroform and filter that into a

50 ml volumetric flask.

Dilute to the mark with chloroform and mix.

For each test sample carry out the complete extraction for a blank determination on

100 ml water.

Measure the absorbance for the test sample as well as for the blank test at 650 nm

against chloroform.

The absorbance of the test sample should not be more than that of the blank.

TEST FOR ALUMINIUM

COLOR COMPARISAN METHOD:

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Apparatus:

Hot plate

Separating funnel – graduate

Nessler cylinder – 50 ml capacity

Chemicals:

Aluminum potassium sulphate AR

Hydrochloric acid

Bromine

Ammonium thiocynate

Amyl alcohol

Ether

Ammonium carbonate

Glycerol

Hemotoxyline

Boric acid

Ammonia solution

Reagents:

Standard Aluminium solution:

Dissolve 1.759 g of Aluminium potassium sulphate in distilled water

containing 50 ml of extractly 5 N hydrochloric acid and dilute to 1 liter (1 ml

= 0.1 mg Aluminium as Al)

Working standards:

Pipette out 10 ml of (1 ml = 0.1 mg) aluminium standard in to 100 ml std

flask with water and make up to the volume mix well. (1 ml = 0.01mg / l Al)

Pipette out 20 ml of (1ml = 0.01 mg) Aluminium standard with 100 ml std

flask with water and make up to the volume mix. (1 ml = 0.002 mg / l Al)

Dilute hydrochloric acid (5N):

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Add 42 ml of conc. Hydrochloric acid (sp.grl1.12) in to 58 ml of distilled

water kept in a 250 ml beaker cool. Mix well.

Bromine Water:

Saturated solution of bromine water.

Ammonium thiocynate (8%) w / v:

Dissolve 20g of Ammonium thio cyanate in 250 ml water, hear if

necessary.

Extraction solvent:

Mix 250 ml of Amyl alcohol and 100 ml of solvent ether.

Glyceric solution:

Dilute 50 ml of glycerin with 50ml distilled water.

Glycerin solution:

Dilute 50 ml of glycerin with 50 ml distilled water.

Hematoxylin Solution:

Weight 0.1 g of hematoxylin and dissolve in 100 ml of cold water

containing 0.1 ml of dilute hydrochloric acid.

Ammonium borate solution (0.8N):

Dissolve 46.5 g of powered boric acid in 500 ml of ammonium hydroxide

(1N) solution. Filter and dilute with distilled water, standardizing against

standard hydrochloric acid.

Ammonium hydroxide 1N solution:

Procedure:

1. Measure 20 ml of sample, blank water into a clean 100 ml conical flask.

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2. Prepare a set of solution (i.e) 1.0, 2.0, 3.0, 4.0, & 5.0 ml of standard aluminium

solution (1ml=0.01mg Al) and dilute to 20 ml with distilled water, the volume of

the solution to be same as that of the sample in all the 100 ml flaks.

3. To each of the series of conical flasks add 1.0 ml of dilute hydrochloric acid

and bromine water (cool the bottle and open) drops until the yellow color persist.

4. Heat to boil and yellow colour should be there till boiling. (other wise add

some more drops)

5. Boil off excess of bromine and cool, then add 1.0 ml ammonium thio cyanate

solution and 10 ml of the extraction solvent.

6. Transfer the contents of each flask to a corresponding 50 ml separating funnel

and shake well.

7. Allow the two layers are separate, collect aqueous layer (water) carefully into

the original conical flask.

8. Wash the solvent layer with 1.0 ml of distilled water and discard the solvent

layer and transfer the contents of 100 ml conical flask in to it.

9. Repeat the extraction process at the end of an extraction is colorless.

10. Finally bring the volume in conical flask to 25 ml with distilled water and

than add ammonium carbonate solution to adjust the pH of the solution to be 7.3

to 7.7.

11. Add 10 ml of glycerin solution and 5 ml of hemotoxylin solution to each flask,

mix and allow to stand for 15 minutes (colour develops)

12. Add 5ml of ammonium borate solution and allow to stand until the magneto

colour of the dye stuff fades out of each solution.

13. After 2 minutes, transfer the solution to a corresponding nessler tube and dilute

to the mark.

14. Compare the sample and blank with the prepared standards of know Aluminum

content.

Calculation:

Aluminium (as Al) mg/l = 1000A (V1-V2) / V3

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A = Amount in mg of aluminum in 1 ml of standard

V1 = Volume in ml of standard required in sample

V2 = Volume in ml of standard required in blank

V3 = Volume in ml of the sample taken for the test.

Chemical Test Procedure Final

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