Flame Colour Inference Golden yellow Na Lilac (violet) K Brick – red Ca Crimson Sr Apple green Ba Bluish green Cu Green Borates Livid blue Pb, Sb, Bi The substance is moistened with conc. HCl, and the mixture, on a platinum wire is shown in the edge of the non-luminous Bunsen flame. Flame test

Dil. Acid group ObservationInference 1. Brisk effervesce, the gas turns lime/Baryta water milky Carbonate is Present. 2. Colourless gas (SO 2 ) with the smell of burning sulphur.The gas turns a filter paper dipped in acidified potassium dichromate green. Sulphite is Present. 3. Colourless gas with the odour of rotten eggs (H 2 S) is evolved. The gas turns lead acetate paper black and cadmium acetate paper yellow. Sulphide is Present. 4. Vineger smell. Red coloration/ppt with neutral ferric chloride. 5. Mix 20 mg of the substance with 1ml of ethyl alcohol and 5 drops of con. H 2 SO 4, Heat in a hot water rack for 10 minutes, and pour into 2 ml of Na 2 CO 3 solution.  Fruity odour Acetate is Present. To about 5 mg of the substance add about 0.5 ml of dil. HCl. Observe the reaction in the cold and then heat it on a water bath.

Conc. Acid group ObservationInference 1. Greenish yellow pungent smelling gas (HCl) which fumes in moist air. Dense white fumes (NH 4 Cl) with a drop of ammonia on a glass rod Chloride is Present. 2. Reddish brown fumes (Br 2 ) are evolved. Bromide is Present. 3. violet vapours (I 2 ) are evolved. Iodide is Present. 4.On warming, brown gas (NO 2 )With characteristic smell is evolved. The brown colour is deepened by the addition of copper turnings. Nitrate is Present. Addition of Conc. H 2 SO 4 + MnO 2, heat

1 A curdy white precipitate (AgCl), insoluble in dil.HNO 3, but soluble in ammonia solution. Chloride is confirmed. 2 A pale yellow precipitate (AgBr), insoluble in dil. HNO 3, but sparingly soluble in ammonia solution. Bromide is confirmed. 3 A yellow precipitate, insoluble in both dil. HNO 3 and ammonium solution. Iodide is confirmed. Silver nitrate group Add silver nitrate to Neutralized sodium carbonate extract

Reddish brown colouration of CCl 4 layer Bromide is confirmed. Violet colouration of CCl 4 layer. Iodide is confirmed. Test for Bromide and Iodide: To the substance in dil. HNO 3 add drops of KMnO 4 solution until the pink colour persists. Add CCl 4 and shake.

A brown ring is formed at the junction of the two layers Nitrate is confirmed. Nitrate : Brown ring test The sodium carbonate extract is acidified with dil. H 2 SO 4. An equal volume of freshly prepared FeSO 4 solution is added. Holding the test-tube in an inclined position con. H 2 SO 4 drops are added without shaking.

A white precipitate insoluble in dil. HCl is formedSulphate is Confirmed Sulphate : BaCl 2 test To the sodium carbonate extract add dil. HCl till no more CO 2 is evolved. Add 1-2 ml of dil. HCl and BaCl 2 solution. A green flame is formedBorate is confirmed. Borate: Flame Test The substance is mixed with calcium flouride and con. H 2 SO 4 to get a paste. Hold some of the paste on a platinum loop, just outside the base of the Bunsen flame.

Phosphate : Amm. Molybdate test To the sodium carbonate extract add dil. HNO 3 ill no more CO 2 is evolved. Add 1-2 ml of amm. Molybdate. Warm. Yellow ppt Phosphate is confirmed. Oxalate Acidify the sodium carbonate extract with dilute acetic acid and add calcium chloride solution. White ppt. Divide the precipitate into two parts – Add dilute HCl  ppt dissolves Add hot dil. H 2 SO 4 and potassium permanganate drop wise  it gets decolourised Oxalate is confirmed

Analysis of Cations Preparation of the original solution A small quantity of the substance (15 mg) is treated with the following solvents in the given order. Distilled water dil.HCl, dil.HNO 3 con.HCl aqua regia (3 vol. con. HCl + 1 vol. con. HNO 3 ). Observe the solubility in the cold, then heat to boiling. If any gases are formed, boil them off. Dissolve 50 to 100 mg of the substance in the suitable solvent and prepare the solution. This solution is often referred to as the original solution.

Group Group reagent CationsPpt formed IDil. HClPb 2+, Ag 1+, Hg 1+ Chlorides IIDil. HCl + H S Pb 2+, Bi 3+, Cd 2+, Cu 2+, Sn 2+, As 3+, Sb 3+ Sulphides IIINH Cl + NH OH Fe 3+, Al 3+, Cr 3+ Hydroxides IVNH Cl + NH OH + H S Co 2+, Ni 2+, Zn 2+, Mn 2+ Sulphides VNH Cl + NH OH + NH CO Ca 2+, Ba 2+, Sr 2+ Carbonates VINo group reagent Mg 2+, NH +, K + -- Cations/ Groups / Group reagents

To 1 ml of the original solution in a centrifuge tube, dil. HCl is added until precipitation, if any, is complete Centrifuge. Residue -1 White, may contain PbCl 2, Hg 2 Cl 2 or AgCl. Group- 1 present Centrifugate-1 Heat on a water bath; pass H 2 S gas until the precipitation is complete. Centrifuge. Residue-2 May Contain Black:HgS, PbS, CuS. Brown:Bi 2 S 3. Yellow:CdS, Sb 2 S 3,SnS 2 Group – 2 present Centrifugate-2 : (Eliminate the interfering anions if necessary.Boil off H 2 S Add 3 drops of con.HNO 3 and boil.Add 100 mg solid ammonium chloride, heat on a water bath. Add ammonia solution till alkaline, and add 2 drops excess. Warm. Stir. Centrifuge. Residue-3: May contain Reddish-brown:Fe(OH) 3 Green:Cr(OH) 3 White:Al(OH) 3 Group 3 Present Centrifugate-3: Add 2 drops of NH 3 solution. Warm. Pass H 2 S to complete precipitation. Centrifuge. Wash the residue Separation of Cations into Groups

Residue-4: May contain Black: CoS, NiS Pink: MnS, White: ZnS Group 4 present Centrifugate-4: Place in a china dish. Acidify with dil. Acetic acid. Evaporate to a pasty mass. Add 5 drops of con.HNO 3.Heat to dryness (till fumes stop) 7 Dissolve the residue in 5 drops of dil. HCl and 1 ml water. Add (in test- tube) 5 drops of 20% NH 4 Cl. Add NH 4 OH with shaking till alkaline. Add excess of 10% (NH 4 ) 2 CO 3 soln. Warm at o C. Centrifuge. Wash. Residue -5 May contain White: BaCO 3,SrCO 3, CaCO 3 Group 5 present Centrifugate-5: Evaporate to a pasty mass, add 0.5 ml con.HNO 3. Heat to dryness White residue- Group-6 present Separation of Cations into Groups Contd….

Separation of group 1 cations: The Residue-1 is washed with cold water containing a few drops of dil. HCl, and centrifuged. To the residue, add 1 ml of hot water. Heat to boiling for 1- 2 minutes. Centrifuge while hot. Transfer the centrifugate quickly to another test tube. Residue (Residue 1.1): White: May contain Hg 2 Cl 2 and AgCl. Wash with boiling water to remove the undissolved PbCl 2.Treat the residue with 0.5 ml warm dilute NH 3 solution. Stir. Centrifuge. Centrifugate (1.1) : May contain PbCl 2. Divide into 3 parts. 1. Cool under tap – White ppt. reappears. – Pb 2+ is confirmed. 2. Add 2 drops of potassium chromate – Yellow ppt. (PbCrO 4 ).- Pb 2+ is confirmed. 3. Add 2 drops of KI solution –Yellow ppt. (PbI 2 ).Boil the ppt. with water and a few drops of acetic acid and cool. The ppt. dissolves on heating and reappears as golden spangles on cooling – Pb 2+ is confirmed. Residue (1.2), Black:Hg + Hg (NH 2 ) Cl. Hg 2 2+ present. Dissolve the ppt. in aqua-regia, heat, divide into two parts. 1. Add stannous chloride - White grayish ppt. Hg 2 2+ is confirmed. 2. Add drops of KI solution­- Red or Yellow ppt. Hg 2 2+ is confirmed. Centrifugate (1.2): May contain Ag (NH 3 ) 2 Cl. Divide into 2 parts. 1. Add dil.HNO 3. White ppt. (AgCl) – Ag 2+ is confirmed. 2. Add KI solution- Yellow ppt. (AgI) –Ag 2+ is confirmed. Analysis of Group I

Residue-2A: May contain Hg 2+, Pb 2, - Bi 3+, Cu 2+ and Cd 2+ Add 1.5 ml dil.HNO 3. Warm and centrifuge. Residue Black: HgS, Wash with Water. Dissolve in 3 drops con. HCl and 1 drop con. HNO 3. Heat. Divide into 2 parts. 1. Add 2 drops SnCl 2.White grey precipitate. Hg 2+ is confirmed 2. Add KI solution Red precipitate. dissolving in excess KI. Hg 2+ is confirmed. Centrifugate-: May contain nitrates of Pb, Bi, Cu, and Cd. Add excess con.NH 3 solution and centrifuge. Residue May contain Bi 3+ and Pb 2+. Add 1ml NaOH solution. Warm. Centrifuge. Centrifugate: May contain Cu 2+, and Cd a) solution is colourless - Cu 2+ is absent. b) Pass H 2 S gas through the solution. Yellow precipitate – Cd 2+ is confirmed. 2. a) Solution is blue – Cu 2+ is present. Divide into 2 parts 1. Add acetic acid in excess and 1 drop [K 4 Fe (CN) 6 ] solution. Red- brown precipitate. Cu 2+ is confirmed. 2. Add KCN (poison) to discharge blue colour. Pass H 2 S. Yellow precipitate. Cd 2+ is confirmed. Residue May be Bi (OH) 3 wash with water. Divide the precipitate into 2 parts. 1. Add sodium stannite reagent. Immediate blackening of precipitate. – Bi 3+ is present. 2. Dissolve in 3 drops of Conc.HNO 3. Pour 1 drop of the solution in 5 ml water- white turbidity- Bi 3+ is confirmed. 3. Dilute the above solution. To one drop, on a spot plate, add a drop of Cinchonine – KI reagent. Orange-red spot- Bi 3+ is confirmed. Centrifugate May contain Pb (OH) 4 -. Acidify with dil. Acetic acid. Divide into 2 parts. 1. Add K 2 CrO 4 solution Yellow precipitate. Pb 2+ is confirmed. 2. Add dil.H 2 SO 4 – white precipitate. Pb 2+ is confirmed. Analysis of Group II A

Residue- May contain HgS. Black: It is tested for Hg as given in the Group 2 A. (Yellow precipitate. of As 2 O 3 also appears here. Centrifugate- May contain HSbCl 4 and H 2 SnCl 6.Take small portions and test as under: 1. Add NH 3 solution till just alkaline. Add 0.3 gms of oxalic acid. Pass H 2 S for 30 seconds. – Orange precipitate. (Sb 2 S 3 )-Sb 3+ is present. 2. To 2 drops of the solution on a spot plate, add a minute crystal of NaNO 2 Stir. Add 2 drops of Rhodamine-B reagent. Violet colouration- Sb 3+ is present. 3. Treat 0.3ml of the solution with 10mg of Mg powder. Add 2 drops of FeCl 3 solution, 3 drops of 5% tartaric acid solution, 2 drops of dimethyl glyoxime reagent, then dil.NH 3 solution until basic. Red colouration. Sn 4+ is present. The centrifugate-2Amay contain Sb 3+ and Sn 2+. Centrifuge. Wash the Residue. Reject washings. Treat the residue with 1ml conc. HCl. Warm on water bath for 3 minutes. Stir. Centrifuge. Analysis of Group II B

Residue: May Contain Fe 3.Dissolve the precipitate in 0.5ml of dil.HNO 3. Add potassium ferrocyanide – Deep blue precipitate.-Fe 3+ is present Confirmatory test for Fe 2+ And Fe To the original solution add ammonium thiocyanate solution. a)No colouration.Fe 2+ is confirmed b)Deep red colouration. Fe 3+ is confirmed. 2. To the original solution Potassium ferrocyanide solution is added. a)Deep blue colour. Fe 3+ is confirmed. b)Pale blue colour. Fe 2+ is confirmed. Centrifugate: May contain NaAlO 2 (colourless), and NaCrO 4 (yellow).(Test only for Al if the solution is colourless. Test portions as under. 1. Add dil. HCl till acidic. Add NH 3 solution. till just alkaline, add 1 drop more. Warm. White Gelatinous precipitate of Al(OH) 3..Al 3+ is present. 2. Centrifuge the above precipitate. Dissolve in dil. HCl, add 0.3ml ammonium acetate solution and1 drop of aluminon reagent. A bright red precipitate. Al 3+ is confirmed. 3. To a drop of the centrifuge-3.1solution on a spot plate, add 1drop of 1% aqueous alizarin-S. Add drops of acetic acid until violet colour appears. Add a few more drops of acetic acid. A red precipitate or colouration appears. Al 3+ is confirmed. 4.Acidify with dil. acetic acid. Add 1 drop of lead acetate solution. Yellow precipitate.(PbCrO 4 ).Cr 3+ present. 5. Acidify with dil. HNO 3, cool, add 0.5ml of amyl alcohol or ether and 2 drops of 3% H 2 O 2.Shake. Allow to stand. The organic layer becomes blue which is unstable. Cr 3+ is confirmed. ANALYSIS OF GROUP III The group III precipitate. (Residue-3) may contain Fe 3, Al 3+ and Cr 3+. Dissolve the precipitate in 2ml of NaOH solution in a boiling tube, add 1ml of 3% H 2 O 2. Boil gently and centrifuge.

Residue: May Contain Co 2+ and Ni 2+. Dissolve the precipitate. in 5 drops of aquaregia. Divide into 3 parts. 1. Add amyl alcohol and 50mg solid NH 4 SCN. Shake. Blue colouration in the alcohol layer – Co 2+ is confirmed. 2. Add drops of 1% alcoholic alpha- nitroso-betanaphthol. Reddish brownprecipitate. Co 2+ is confirmed. 3. Add 1 drop of NH 4 Cl solution. Make it faintly alkaline with NH 3 solution. Add 3-5 drops of dimethyl glyoxime reagent. Redprecipitate. Ni 2+ is confirmed. Centrifugate: May contain Mn 2+ and Zn 2+. Boil off to expel H 2 S Cool. Add excess of NaOH solution until basic and 4 drops of 3% H 2 O 2 solution. Warm for 3 minutes. Centrifuge. Residue-4.2: May contain Mn 2+. Dissolve in 1ml dil.HNO 3. Divide into 2 parts. 1. Add 2 drops of 3% H 2 O 2. Warm to decompose excess H 2 O 2. Cool. Add 50 mg NaBiO 3. Shake. Allow to stand. The solution turns purple – Mn 2+ is confirmed. 2. Take the other part in a boiling tube with 0.5 ml H 2 O. Add 2 drops of 3% H 2 O 2. Boil to decompose excess H 2 O 2. Cool. Add 0.5ml con.HNO 3 and 250mg PbO 2. Boil. Allow to stand – A purple solution is formed. Mn 2+ is confirmed. Centrifugate-4.2: May contain Zn 2. Divide into 3 parts. 1. Pass H 2 S. White precipitate. (ZnS). Zn 2+ is confirmed. 2. Just acidify with dil. H 2 SO 4, add 5 drops of 0.1% CuSO 4 solution and 5 drops of ammonium mercury thiocyanate reagent. Stir. Violet precipitate. Zn 2+ is confirmed. 3. Just acidify with dil.H 2 SO 4. Add a drop of dil. cobalt nitrate solution, 0.5ml of ammonium mercury-thiocyanate reagent. Stir. Pale blue precipitate. Zn 2+ is confirmed. ANALYSIS OF GROUP IV The group IV precipitate (Residue-4) may contain Co 2+, Ni 2+, Mn 2+ and Zn 2. If not black, Co 2+ and Ni 2+ are absent. Stir the precipitate in the cold, with very dil. HCl. Centrifuge.

Part 1 Add a few drops of K 2 Cr 2 O 7  Yellow ppt of BaCrO 4. Ba 2+ is confirmed. Dissolve the residue in a few drops of conc. HCl, Apply flame test. Yellowish green flame. Ba 2+ is confirmed. Part 2 To 1ml of the solution add1ml of saturated ammonium sulphate solution followed by 0.1 g sodium thiosulphate. Heat on water bath for 5 minutes. White ppt. of SrSO 4, Sr 2+ is present. Add a few drops of conc. HCl to the ppt, apply flame test. Crimson flame. Sr 2+ is confirmed. Part 3 Divide into two parts - 1. Add NH 3 solution to get the smell of ammonia. Add ammonium oxalate solution. Warm. White precipitate. Ca 2+ is confirmed. 2. The other portion is evaporated to a pasty mass. Add 1 drop of conc. HCl. Apply flame test. Brick-red flame. Ca 2+ is confirmed. ANALYSIS OF GROUP V The group V precipitate. (Residue-5) may contain Ba 2+, Ca 2+ and Sr 2+. Dissolve the precipitate in 1 ml of dil. acetic acid. Warm. Divide into three parts and test as follows.

1. Add 3 drops NH 4 Cl, and NH 4 OH till alkaline. Add 4 drops of Na 2 HPO 4. White precipitate. Mg 2+ confirmed. 2. Add 2 drops of Magneson reagent and NaOH solution drops till alkaline. A blue precipitate. Mg 2+ is confirmed. 3. Add a few drops of 2% oxine solution ( 8 – hydroxyquinoline). Warm. Pale yellow precipitate of Mg oxinate. Mg 2+ Present. ANALYSIS OF GROUP VI The centrifugate from Group VI is evaporated to dryness. A white residue is obtained. Group VI cations are present. Dissolve in a few drops of dil. HCl. Add 1ml of water. Divide into 3 parts.