Salt Analysis

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EXPERIMENT I 1

Colour

2

Appearance

SYSTEMATIC PROCEDURE FOR SIMPLE SALT ANALYSIS OBSERVATION INFERENCE PRELIMINARY TESTS May be due to lead, ammonium, Colourless aluminium, zinc, magnesium, barium salts Brown May be due to ferric salt Pale green May be due to ferrous salt Blue May be due to cupric salt Dark green May be due to cupric or nickel salts Pale pink May be due to manganese salts Crystalline solid May be due to chloride, bromide, iodide, sulphate, nitrate, sulphite, acetate salts Amorphous solid

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4

Solubilty:A pinch of the sample was taken in a test tube and shaken with 2mL of water

Water soluble

Water insoluble

May be due to carbonate and sulphide salts May be due to chloride, bromide, iodide, sulphate, nitrate, sulphite, acetate salts May be due to carbonate and sulphide salts

Action of heat:A small Reddish brown gas with fishy odour amount of the sample is evolved, turning starch iodide paper blue Presence of nitrate taken in a dry test tube and Colourless, odourless gas evolved, turning heated strongly Presence of carbonate lime water milky Blue colour of the substance turned white Presence of copper sulphate Reddish brown gas with fishy odour Presence of lead nitrate evolved with crackling sound Colourless gas with pungent smell evolved and deposited as white solid on the cooler Presence of ammonium salt parts of the test tube Yellow when hot and white when cold Presence of zinc salt No characteristic change Absence of nitrate, carbonate, CuSO4, Pb(NO3)2, ammonium, zinc salts Bluish green flame Apple green coloured flame Brick red coloured flame Crimson red coloured flame No characteristic coloured flame

5

Flame Test:A small quantity of the sample was taken ina watch glass and 2 drops of conc. HCl was added to make a paste of it . The paste was taken in a charred tip of the splinter and shown to non-luminous flame

Presence of cupric salt Presence of barium salt Presence of calcium salt Presence of strontium salt Absence of cupric, barium, calcium, strontium salts

6

Ash test:To a small portion Thenard's blue coloured ash was obtained Presence of aluminium salt of the salt soln., 1mL of cobalt nitrate soln and few Rinmann's green coloured ash was Presence of zinc salt drops conc. Nitric acid were obtained added. A filter paper was soaked in this soln. and burnt to ashes.

6

Ash test:To a small portion of the salt soln., 1mL of cobalt nitrate soln and few drops conc. Nitric acid were added. A filter paper was soaked in this soln. and burnt to ashes.

Rinmann's green coloured ash was obtained Pink coloured ash was obtained No characteritic coloured ash

Presence of zinc salt Presence of magnesium salt Absence of aluminium, zinc, magnesium salt

II SYSTEMATIC ANALYSIS OF ANIONS Colourless, odourless gas evolved with a 1 Dil HCl test: To a small Presence of carbonate salts quantity of the sample, 1mL brisk effervescence, turning lime water milky of dil. HCl was added Colourless gas with rotten egg smell evolved, turning lead acetate paper black Presence of sulphide salts Colourless, odourless gas with suffocating smell evolved, turning acidified potassium Presence of sulphite salts dichromate paper green No characteristic change 2

3

4

5

Conc. H2SO4 test: To a small quantity of the substance, 1mL of conc. Sulphuric acid was added and heated

Colourless gas with irritating smell evolved, gigving dense white fumeswith a glass rod dipped in NH4OH A reddish brown gas with irritating smell evolved, turning starch iodide paper first blue and then yellow Violet vapour evolved, turning starch iodide paper blue A reddish brown gas with fishy odour evolved, turning starch iodide paper blue

No chracteristic change MnO2 test: To a small A greenish yellow gas evolved, turning quantity of the sample, a starch iodide paper first blue then pinch of MNO2 was added colourless followed by the addidtion of 1mL conc. H2SO4 and No chracteristic change heated strongly Copper turning test: To a small quantity of the substance, a copper turning and 1mL conc. H2SO4 were added and heated strongly Chromyl chloride test: To a small quantity of the sample, a pinch of crystalline potassium dichromate, 1mL conc. H2SO4 were added and heated strongly

A reddish brown gas with fishy odour evolved, turning starch iodide paper blue. The Colour of the soln. turned green No chracteristic change

Absence of carbonate, sulphide, sulphite salts Presence of chloride

Presence of bromide Presence of iodide Presence of nitrate Absence of chloride, bromide, iodide, nitrate salts Presence of chloride

Absence of chloride

Presence of nitrate

Absence of nitrate

Red vapour of chromyl chloride evolved giving yellow soln. on passing to NaOH Presence of chloride soln. On adding lead acetate soln., yellow precipitate was obtained No characteristic change

Absence of chloride

5

III

1

Chromyl chloride test: To a small quantity of the sample, a pinch of crystalline potassium dichromate, 1mL conc. H2SO4 were added and No characteristic change heated strongly

ANALYSIS USING SODIUM CARBONATE EXTRACT PREPARATION OF SODIUM CARBONATE EXTRACT: To 1g of the substance, 3g of sodium carbonate and 5mL of water was added and boiled for about 5 minutes and then centrifuged. The clear solution (centrifugate) is the required sodium carbonate extract, using which the following tests wre carried out Silver nitrate test: to 1mL of the Na2CO3 extract dil. HNO3 was added till effervescence ceases and then 1mL of AgNO3 soln. was added

Curdy white precipitate was obtained which is completely soluble in excess of NH4OH Pale yellow precipitate was obtained which is partially soluble in excess of NH4OH Yellow precipitate was obtained which is insoluble in excess of NH4OH No characteristic change

2

3

4

5

Absence of chloride

Presence of chloride

Presence of bromide Presence of iodide Absence of chloride, bromide, iodide salts

Barium chloride test: To 1mL of the Na2CO3 extract dil. HCl was added till effervescence ceases and then 1mL of BaCl2 solution was added

White precipitate was obtained which is insoluble in hot conc. HCl acid White precipitate was obtained which is soluble in hot conc. HCl acid No characteristic change

Absence of sulphate and sulphite

Lead acetate test: To 1mL of the Na2CO3 extract dil. Acetic acid was added till effervescence ceases and 1mL of lead acetate soln. was added

White precipitate was obtained which is soluble in excess of ammonium acetate

Presence of sulphate

Black precipitate was obtained

Presence of sulphide salts

No characteristic change

Absence of sulphate and sulphide

Brown ring test: To 1mL of the Na2CO3 extract dil. H2SO4 was added till effervescence ceases and equal volume of freshly prepared FeSO4 soln. was added, followed by the addition of 1mL of conc. H2SO4 along the sides of the test tube.

Presence of sulphate Presence of sulphite

Brown ring was obtained at the junction of Presence of nitrate two layers

No characteristic change

Sodium nitroprusside test: To 1mL of the Na2CO3 Violet colouration was seen extract, 1mL of sodium nitroprusside soln. was added No characteristic change

Absence of nitrate

Presence of sulphide salts

Absence of sulphide

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6

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IV 1

2

V

Sodium nitroprusside test: To 1mL of the Na2CO3 extract, 1mL of sodium nitroprusside soln. was added No characteristic change Acidified KMnO4 test: To 1mL of the Na2CO3 Purple colour of KMnO4 was discharged extract, dil. H2SO4 was added till effervescence ceases and a few drops of acidified KMnO4 soln. was No characteristic change added Chlorine water test: To 1mLm of the Na2CO3 extract, 1mL of chlorine water was added

Absence of sulphide

Presence of sulphide salts

Absence of sulphide

Yellow colouration was seen

Presence of bromide

Violet colouration was seen

Presence of iodide

No characteristic change

Absence of bromide and iodide

SYSTEMATIC ANALYSIS OF CATIONS TEST FOR ZERO GROUP CATION NaOH test: To a small quantity of the given Colourless gas with pungent smell sample, 1mL of NaOH soln. evolved, giving dense white fumes with a Presence of ammonium salt was added and warmed glass rod dipped in conc. HCl acid Nessler's Reagent test: To the above mixture, 1mL of Nessler's reagent was added Brown precipctate was obtained

Presence of ammonium salt confirmed

PREPARATION OF SALT SOLUTION For water-soluble salts: Dissolve a small quantity of the substance in 5 mL of water For water-insoluble salts: Dissolve a small quantity of the substance in 2 mL of dil. HCl GROUP IDENTIFICATION

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Test for group I cation: White precipitate was obtained To 1ml of the salt soln., 1mL of dil. HCl was added No characteristic change Test for group II cation: To the above mixture of group I, 1mL of H2S soln. was added

Presence of group I cation Absence of group I cation

Black precipitate was obtained

Presence of group II cation

No characteristic change

Absence of group II cation

Test for group III cation: Green / Brown / Gelatinous whie To 1mL of the salt soln., precipitate was obtained 1mL each of NH4OH and NH4Cl solns were added No characteristic change Test for group IV cation: Dirty / Buff / Black precipitate was To the above mixture of obtained group III, 1mL of H2S soln was added

Presence of group III cation Absence of group III cation Presence of group IV cation

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Test for group IV cation: Dirty / Buff / Black precipitate was To the above mixture of obtained group III, 1mL of H2S soln was added No characteristic change Test for group V cation: To 1mL of the salt soln., 1mL each of NH4Cl , Nh4OH and (NH4)2CO3 solns were added

1 2 3 4 5 6

PRECIPITATE OF Group I Group II Group III Group IV Group V Group VI

Presence of group V cation

No characteristic change

Absence of group V cation

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4

To 1mL of the salt soln., 1mL of potassium chromate Yellow precipitate was obtained soln. was added To 1mL of the salt soln., 1mL of potassium iodide soln. was added To 1mL of the salt soln., 1mL of H2S soln. was added

To 1mL of the salt soln., 1mL of potassium ferrocyanide soln. was added

Absence of group VI cation

Presence of Pb^2+ confirmed

Presence of Pb^2+ confirmed

Yellow precipitate was obtained which dissolved on heating and reappeared as golden yellow spangles on cooling

Presence of Pb^2+ confirmed

Black precipitate was obtained

Presence of Pb^2+ confirmed

ANALYSIS OF GROUP II CATION 1 To 1mL of the salt soln., excess of NH4OH soln. was Deep blue coloured soln. was obtained added 2

Presence of group VI cation

CONFIRMATORY TESTS FOR CATIONS SOLVENT USED TO DISSOLVE THE PRECIPITATE Hot water 10 drops of conc. HNO3 , heated and then diluted Dilute HCl 10 drops of conc. HNO3 , heated and then diluted Dilute acetic acid No solvent used

ANALYSIS OF GROUP I CATION 1 To 1mL of the salt soln., 1mL of dil. H2SO4 was White precipitate was obtained added 2

Absence of group IV cation

White precipitate was obtained

Test for group VI cation: To 1mL of the salt soln., White precipitate was obtained 1mL each of NH4Cl , NH4OH and Na2HPO4 solns were added No characteristic change

VI

Presence of group IV cation

Reddish brown precipitate was obtained

Presence of Cu^2+ confirmed

Presence of Cu^2+ confirmed

2

To 1mL of the salt soln., 1mL of potassium ferrocyanide soln. was added

Reddish brown precipitate was obtained

ANALYSIS OF GROUP III CATION IF GREEN PRECIPITATE WAS OBTAINED, 1 To 1mL of the salt soln., 1mL of acidified KMnO4 Pink colour of KMnO4 was discharged soln was added 2

1

2

1

2

3

Presence of Cu^2+ confirmed

Presence of Fe^2+ ions confirmed

To 1mL of the salt soln., 1mL of potassium ferricyanide soln was added Deep blue coloured soln. was obtained

Presence of Fe^2+ ions confirmed

IF BROWN PRECIPITATE WAS OBTAINED, To 1mL of the salt soln., 1mL potassium thiocyanate soln. was added Blood red coloured soln. was obtained

Presence of Fe^3+ ions confirmed

To 1mL of the salt soln., 1mL of potassium ferrocyanide soln. was added

Prussian blue coloured precipitate was obtained

IF GELATINOUS WHITE PRECIPITATE WAS OBTAINED, To 1mL of the salt soln., 1mL each of NH4OH and aluminon reagent was added Bright red lake was obtained

To 1mL of the salt soln., a few drops of NaOH soln was added

White precipitate was obtained which dissolves on adding excess of NaOH soln

Presence of Fe^3+ ions confirmed

Presence of Al^3+ ions confirmed

Presence of Al^3+ ions confirmed

Ash test:To a small portion of the salt soln., 1mL of cobalt nitrate soln and few drops conc. Nitric acid were Thenard's blue coloured ash was obtained Presence of Al^3+ ions confirmed added. A filter paper was soaked in this soln. and burnt to ashes.

ANALYSIS OF GROUP IV CATIONS IF BLACK PRECIPITATE WAS OBTAINED, 1 To 1mL of the original salt soln., 1mL of ammonium hydroxide and 1mL of Pink coloured precipitate was obtained dimethyl glyoxime solutions were added

Presence of Ni^2+ ions confirmed

1

1

1

2

3

To 1mL of the original salt soln., 1mL of ammonium hydroxide and 1mL of Pink coloured precipitate was obtained dimethyl glyoxime solutions were added IF BUFF COLOURED PRECIPITATE WAS OBTAINED, The precipitate of group IV was centrifuged and to it , 1mL of conc. Nitric acid was added , followed by the Purple coloured solution was obtained addition of a pinch of sodium bismuthate IF DIRTY WHITE PRECIPITATE WAS OBTAINED, To 1mL of the salt soln., a few drops of NaOH soln White precipitate was obtained which was added dissolves on adding excess of NaOH soln To 1mL of the original soln., 1mL of potassium ferrocyanide soln. was added

Greenish white precipitate was obtained

Ash test:To a small portion of the salt soln., 1mL of cobalt nitrate soln and few drops conc. Nitric acid were Rinmann's green coloured ash was added. A filter paper was obtained soaked in this soln. and burnt to ashes.

ANALYSIS OF GROUP V CATIONS 1 To 1mL of the salt soln., Yellow precipitate was obtained 1mL of potassium chromate soln. was added No yellow precipitate was obtained 2

3

To 1mL of the salt soln., White precipitate was obtained 1mL of ammonium sulphate was added No white precipitate was obtained To 1mL of the salt soln., 1mLof ammonium oxalate soln. was added

White precipitate was obtained

ANALYSIS OF GROUP VI CATIONS 1 To 1mL of the salt soln., a few drops of NaOH soln White precipitate was obtained which was added dissolves on adding excess of NaOH soln 2

Ash test:To a small portion Pink coloured ash was obtained of the salt soln., 1mL of cobalt nitrate soln and few drops conc. Nitric acid were added. A filter paper was soaked in this soln. and burnt to ashes.

Presence of Ni^2+ ions confirmed

Presence of Mn^2+ ions confirmed

Presence of Zn^2+ ions confirmed

Presence of Zn^2+ ions confirmed

Presence of Zn^2+ ions confirmed

Presence of Ba^2+ ions confirmed Absence of Sr^2+/Ca^2+ ions Presence of Ba^2+/Sr^2+ ions confirmed Absence of Ca^2+ ions Presence of Sr^2+/Ca^2+ ions confirmed

Presence of Mg^2+ ions confirmed Presence of Mg^2+ ions confirmed

2

Ash test:To a small portion Pink coloured ash was obtained of the salt soln., 1mL of cobalt nitrate soln and few drops conc. Nitric acid were added. A filter paper was soaked in this soln. and burnt to ashes.

3

To 1mL of the original soln., a few drops of Magneson reagent was added

Blue coloured precipitate was obtained

REPORT : The given simple salt contains (i) anion : ....................................................................... (ii) cation : .......................................................................

Presence of Mg^2+ ions confirmed

Presence of Mg^2+ ions confirmed

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