Inorganic Qualitative Analysis Systematic Analysis of Anion S.No Experiment Observation Inference 1 Preliminary Reactions Colourless Absence of Fe2+, Fe3+, Ni2+, Co2+

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Systematic Procedure for Inorganic Qualitative Analysis Systematic Analysis of Anion S.No Experiment Observation Inference 1 Preliminary Reactions Colourless Absence of Fe2+, Fe3+, Ni2+, Co2+. Appearance Green May be Fe2+, Ni2+, Cu2+ Blue Cu2+ Brown May be Fe2+ Pink May be Co2+, Mn2+ A colourless gas with a May be NH4+ salt characteristic pungent Action of heat odour turning moist red Take a small amount of litmus paper blue. the given salt taken in a Reddish brown vapours May be 2 dry test tube, heat it turning acidified ferrous gently; then strongly. sulphate paper brown, are obtained. Substance is white when May be (Zn)2+ cold and yellow when hot. 3 Flame Test (i) Bluish green flame May be Cu2+ To a small amount of the (ii) Apple green May be Ba2+ given salt taken in a (iii) Brick red May be Ca2+ watch glass, add a drop (iv) Crimson red May be Sr2+ of Con. HCl and make it into a paste. Introduce the paste with the help of a glass rod to the base of the non-luminous bunsen burner. Identification of Anions from Volatile Products: Brisk effervescence of Anion is CO32- colourless, odourless gas turning lime water, milky is obtained. Colourless gas with a smell Anion is sulphide. of rotten eggs, turning lead acetate paper black is obtained. Colourless gas with smell of Anion is SO32- burning sulphur turning Action of dilute H SO : 2 4 acidified dichromatic green To a small portion of the is obtained. given salt taken in a test 4 Reddish brown gas with Anion is tube add 1 or 2ccs of fishy odour turning H SO and gently warm 2 4 acidified ferrous sulphate it. brown is obtained. Colourless gas with smell of Anion may be acetate. vinegar is obtained. 2- 2- No characteristic Absence of CO3 , , S , 2- - observation. SO3 , CH3COO

Reddish brown vapours Anion may be bromide. turning moist fluorescent paper red. Colourless gas with Anion may be chloride. pungent smell giving dense Action of Con.H2SO4 white fumes with a glass To a small amount of rod dipped in NH4OH given salt taken in a test solution. 5 tube, add 2-3 ccs of Violet coloured vapours Anion may be Iodide. Con.H2SO4 and gently turning starch paper blue heat it. or violet. Reddish brown vapours Anion may be nitrate. turning acidified ferrous sulphate paper brown.

No characteristic Absence of , , & observation. 6 Action of Con.H2SO4 with Copius evolution of reddish Anion is nitrate. Cu turnings: brown gas turning acidified Mix a small amount of ferrous sulphate paper the given salt taken in a brown is observed. test tube with a few Cu

bits, add 2 – 3 ccs of No reddish brown vapours. Absence of H2SO4 and heat it. A greenish yellow gas Anion may be chloride. Action of Con.H2SO4 with turning starch iodide paper MnO2 violet (or) blue is obtained. To a small amount of the Reddish brown vapours Anion may be bromide. given salt taken in a test turning moist fluorescent 7 tube, add an equal paper red is obtained. amount of MnO2 and Violet vapours turning Anion may be iodide add a few ccs of starch paper blue (or) violet Con.H2SO4 and gently is obtained. heat. No characteristic coloured Absence of , , vapours are obtained. 8 Action of NaOH A colourless gas with a Cation is ammonium. To a pinch of the given pungent smell giving dense salt taken in a test tube, white fumes with glass rod add few ccs of 10% dipped in HCl is obtained. NaOH solution and gently warm it. No characteristic gas is Ammonium is absent. Ammonium liberated. Sodium Carbonate Extract Identification of Anions in solution Preparation of Extract:

Take about or of the given salt in a 50cc beaker. Mix it well with about thrice its amount of solid sodium carbonate. Add about 15 – 20ml of distilled water. Mix well with neat glass rod. Boil contents of the beaker over Bunsen flame. Cool and filter through filter assembly. Collect the clean filtrate in another beaker. The Filtrate is called soda extract.

S.No Experiment Observation Inference 9 Silver Nitrate Test: Curdy white precipitate Anion is Cl– To a portion of extract soluble in NH4OH. add dilute HNO3 until effervescence ceases. Pale yellow precipitate Anion is Br– Add few drops in excess, sparingly soluble in NH4OH. 2 – 3nos of AgNO3

solution. Yellow precipitate insoluble Anion is in NH4OH.

No precipitate is obtained. Absence of Br–, Cl–, I–

10 Barium Chloride Test: A white precipitate Anion is To about one or two ccs insoluble in HCl. of the extract, (after

neutralizing with acetic A white precipitate soluble Anion is acid and boiling of CO2) in HCl. add BaCl2 solution.

To a portion of the above No precipitate is obtained. Absence of ppt add dil. HCl.

11 Lead Acetate Test:

To about one or two ccs White ppt, soluble in excess confirmed. of the extract (after of ammonium acetate acidifying with acetic solution. acid, boiling off CO2 and cooling) add lead acetate solution. 12 Ferrous Sulphate Test: (Brown Ring Test)

To about 1 or 2cc of A brown ring is obtained at Anion is extract add dilute the junction of the liquid. H2SO4 in drops until the effervescence ceases. And few drops in excess

add 2- 3 drops of freshly No brown ring is observed. Anion is absent. prepared FeSO4 solution. Keeping the test tube in a slanting position, add Con. H2SO4 without disturbing the solution. 13 Ferric Chloride Test:

Take about 1 or 2ccs of Deep red colouration confirmed. the extract in a test tube produced and add neutral FeCl3 solution. Filter, if required, and divide the solution or the filtrate in two parts:

(i) To one part add Red colouration disappears confirmed. dil.HCl

(ii) To the second part Reddish brown ppt. confirmed. add water and boil

14 Calcium Chloride Test: To a portion of the A white precipitate of Confirms Oxalate. sodium carbonate calcium oxalate is obtained extract, taken in a test tube add dil. Acetic acid and boil off CO2. Then add a few drops of calcium chloride solution.

Add dil. HNO3 to the The precipitate dissolves. white ppt and warm. 15 Ethyl Acetate Test: To a pinch of given salt A pleasant fruity odour is The presence of anion acetate is taken in a test tube, add obtained. confirmed. a few drops of ethanol followed by 1 or 2ccs of H2SO4. Gently heat and cool it. Pour into Na2CO3.

Systematic Analysis of Cations Preparation of Original solution: Check solubility of the given salt in: - Cold water (or) hot water (or) Dil HCl (or) Conc. HCl. Label this solution as original solution.

Procedure for Separation of Basic Radicals into Groups To the original solution, add Dil. HCl.

White ppt. Group I present (Pb2+ and If no ppt. pass H2S through the given solution. If a coloured ppt. is formed, group 2 cations are present (Cu2+), Pb2+. If no ppt is obtained from the above, boil off H2s gas and add a few drops of conc. HNO3 to the remaining solution. Cool, add 2-3g of solid NH4Cl. Boil again and add NH4OH solution till it becomes alkaline. If a ppt is formed, Group III cations are present. Reddish brown ppt. Fe3+ Gelatinous white ppt. Al3+

If no ppt., pass H2S to the given solution.

If a ppt is formed Group IV cations are present. Black ppt. (Co2+, Ni2+) Flesh coloured ppt. Mn2+ white ppt. Zn2+. If no ppt is formed, boil off H2S gas add (NH4)2CO3 solution. If a white ppt is formed Group V cations are present (Ba2+, Sr2+, Ca2+) If no ppt. Group VI cation is present (Mg2+

If none of the cations are present, check for Group 0 ( )

Cation Analysis

Group O (NH4+):

To a pinch of given salt add Yellowish brown precipitate Cation is ammonium. some water and warm. is obtained. Then allow it to cool. Add Nessler’s reagent and No precipitate is obtained. Cation is not ammonium. excess of NaOH solution.

Group I (lead):

Group I precipitate is dissolved by heating the precipitate with dil.HNO3 or distilled water. Divide the solution into 3 portions and carry out the following reactions. Experiment Observation Inference To one portion of the above A white precipitate of Pb2+ is present. solution add dilute H2SO4. PbSO4 is obtained.

To another portion, add A yellow precipitate of Presence of is potassium chromate is obtained. confirmed. solution.

Golden Spangles Test: A yellow precipitate is The presence of is To the 3rd portion, add KI obtained. confirmed. solution

To above yellow precipitate, Precipitate dissolves and add some H2O, boil and reappears in the form of then cool. golden spangles.

Group II ( : The group 2 precipitate is dissolved by heating with dilute HCl. Precipitate dissolves.

Experiment Observation Inference Test for : To one portion of the above A pale blue precipitate The presence of Cu2+ is solution add drops of which dissolves in excess confirmed. NH4OH, until it is in NH4OH to give any inky excess. blue solution is obtained.

To another portion, add dilute acetic acid and A chocolate brown ppt. Confirms copper. potassium ferrocyanide [K4(Fe(CN6))]

Group III: Group III precipitate is heated with Con. HCl and water, cooled and filtered. Reddish brown precipitate indicates Fe2+ (or) Fe3+ Gelatinous white indicates Al3+

Experiment Observation Inference 1. To 1 cm3 OS, add a Formation of a deep Fe2+ confirmed. few drops of dilute blue colour or ppt. HCl and then add 0.5 cm3 of potassium ferricyanide solution. 2. White gelatinous Formation of a blue Al3+ confirmed. precipitate dissolves floating ppt. in in minimum quantity colourless solution. of dil. HCl. To this, (This is known as Lake add a few drops of test) blue litmus solution.

Add NH4OH solution A blue ppt., suspended in excess. in a colourless medium (called a lake)

2B To one part of the White Precipitate soluble Al3+ confirmed above solution add in excess of NaOH NaOH solution solution

3. Reddish brown ppt. A yellow solution is may be present. (Shows the presence produced. of Fe3+) Treat it with minimum quantity of dil. HCl solution to dissolve the ppt. and then heat. Divide the solution into two parts. (i) To one part, add few A deep blue colour or confirmed. drops of potassium ppt. is obtained. ferrocyanide solution.

(ii) To another portion A deep red colour is confirmed. add few drops of obtained. potassium sulphocyanide solution.

Group IV :

Group IV precipitate is warmed with dilute HCl centrifugate Black precipitate Ni2+ Ni is not soluble in dilute HCl. To residue A Red rosy precipitate confirms the add Con.HCl, boil, cool. Divide the presence of Ni2+ solution into two parts and boil of H2S. To one part add dimethyl glyoxime reagent. Con.NH4OH, till the solution becomes alikaline. Sodium Hydroxide and Br2 – water test. A black precipitate confirms the presence To the second part of the above solution, of Ni2+. add NaOH and Br2 water and then boil Confirmation of Zn2+: Dissolve a part of white ppt in dil. HCl. Boil off H2S and divide the solution in two parts. Bluish White ppt confirms Zinc. (i) To one part of solution add Pot. ferrocyanide solution White ppt soluble in excess of NaOH is (ii) To second part of solution add NaOH. obtained. Flesh (buff) colour precipitate indicates A white precipitate is formed. Add Br Mn2+. water to the white ppt it turns black or Dissolve the precipitate in Dil. HCl and brown. Mn2+ confirmed. boil off H2S then add NaOH solution. Lead peroxide test A pink colouration is produced. Mn2+ is To the second part of the flesh coloured confirmed. ppt, add a little of PbO2 powder and conc. HNO3. Boil, cool and allow to stand.

Group V : Take a small portion of Group V precipitate, carry out flame test. Take group V precipitate, add dilute CH3COOH, warm. Boil of CO2 and divide the solution into three parts.

Barium, Ba2+ Stronium Sr2+ Calcium Ca2+ 1. Potassium chromate 1. Ammonium sulphate 1. Ammonium oxalate test. test. test. To the third portion of the To one part of the above To the second part of the above solution, add solution, add a few drops of above solution add a few ammonium oxalate K2CrO4 solution – Yellow drops of ammonium solution and then NH4OH ppt. Ba2+ confirmed. sulphate solution – white solution to make it alkaline ppt. Sr2+ confirmed. and scratch the sides of the test tube – white ppt. Ca2+ confirmed.

2. Dil. H2SO4 Test Flame test Flame test To another portion of the above solution, add a few drops of dil. H2SO4 – white ppt. insoluble in HCl. Ba2+ confirmed.

Test for Mg2+:

1. Ammonium phosphate test. White crystalline ppt. To the original salt solution, add solid NH4Cl, warm to dissolve, cool and add NH4OH solution in slight excess. Then add ammonium phosphate solution, shake well and allow to stand 2. To the original sat solution, add White crystalline ppt confirms Mg2+ disodium hydrogen phosphate.

Additional Test: Ash test for Al3+, Zn2+, Mg2+

To a pinch of given salt Blue tinted ash is obtained. The presence of Al3+ is taken in a test tube, add a confirmed. few drops of Con.H2SO4, Green tinted ash is Co(No3)2. Mix it well. Dip obtained. The presence of Zn2+ is one filter paper bit in a confirmed. Bunsen flame. After it Pink tinted ash is obtained. burns remove it from The presence of Mg2+ is flame. After cooking confirmed. observe the odour of the ash formed.

READY REFERENCE CHART FOR QUALITATIVE ANALYSIS OF BASIC RAIDCALS Make the solution of the given salt in distilled water, in dil. HCl or conc. HCl, cold or hot. Label it original solutions (O.S.). To the O.S., add dil. HCl White ppt. 2+ If Group I is absent, pass H2S gas through O.S. for sufficient time after acidification with dil. HCl filter. (Pb ) PPt. - Group II If Group II is absent, add solid NH Cl, 0.5 ml conc. HNO to the O.S. Boil and cool. Add NH OH till it smells of ammonia. If a ppt. is formed, group III is present. Confirmation 2+ 2+ 4 3 4 2+ Black ppt. - (Pb , Cu ) Reddish brown ppt. - of Pb 3+ 3+ If group III is absent, through a part of the solution obtained in group III pass H2S gas. If a ppt. is obtained group IV is present. Yellow ppt. - (As ) (Fe ) 2+ Boil white ppt. White ppt. - (Zn ) If Group IV is absent, to the O.S. add solid NH Cl, NH OH and Dissolve the black ppt. in minimum 3+ 4 4 with distilled White ppt. - (Al ) 2+ 2+ Black ppt. - (Ni and Co ) water and quantity of 50% HNO3. To one part of Confirmation of (Fe3+) (NH4)2CO3 solution. 2+ divide the Dissolve the brown ppt. Flesh coloured ppt. - (Mn ) solution into the above solution add. dil. H2SO4 in dil. HCl and divide the 2+ 2+ 2+ 2+ If Group V is absent two parts. and alcohol. If a white ppt. is formed Confirmation of Zn White ppt. (Ba , Sr , Ca ) 2+ solution into two parts. 2+ (i) Add KI solution Pb is indicated. If no white ppt.(i) is To one part of solution Dissolve a part of white ppt. in dil. HCl and divide the solution in two Dissolve a part of white ppt. in dil. acetic test for Mg . to one part of add pot. ferrocyanide parts. (i) To the O.S. add a acid. Boil off CO2. above formed, add excess NH4OH to the solution. A prussion (i) To one part of solution add. pot. ferrocynaide solution - (i) To one part of the above solution, add pinch of NH4Cl, a few solution. second part of the solution - Blue blue colour or ppt. Bluish white ppt. 2+ Yellow ppt. (ii) To second part of (ii) To second part of solution add NaOH solution. White ppt. K2CrO4 solution. Yellow ppt. Confirms groups of NH4OH 2+ coloured solution indicates Cu . solution add. pot. soluble in excess. 2+ and excess of amm. confirms Pb . 2+ Ba . Confirmation of Cu sulphocyanide solution. Confirmation of Ni2+ and Co2+ 2+ phosphate solution - (ii) Add K2CrO4 A blood red colouration. 2+ 2+ 2+ (i) Add excess of NH OH solution to (ii) If Ba is absent, then to the second part solution to the 4 3+ If the ppt. obtained is black Ni or Co is indicated. Note the colour White ppt. - Mg . original solution. Deep blue solution. Confirmation of Al 2+ of above solution add amm. sulphate(ii) Perform charcoal second part of of the salt. If the salt is greenish - Ni is indicated and if the salt is 2+ (ii) Acidify the above deep blue solution(i) Perform charcoal cavity - solution. A white ppt. confirms Sr . cavity cobalt nitrate the above 2+ solution. with dil. acetic acid. Add Pot. cobalt nitrate test with purple Co is indicated. 2+ 2+ test with white ppt. - (iii) If both Ba and Sr are absent, then to Yellow ppt. ferrocyanide solution. Chocolate white ppt. Blue mass. 2+ A pink mass. 2+ (ii) Lake test. White ppt. + Confirmation of Co the third part of the above solution add + 2+ brown ppt. confirms Cu . Test for NH confirms Pb . dil. HCl + a few drops of ammonium oxalate solution. A white 4 (i) (i) Take O.S. and neutralise the acid by adding NH OH. Add a 2+ To the salt and blue litmus solution + 4 ppt. confirms Ca . pinch of potassium nitrite and acidify with dil. acetic acid - sodium hydroxide NH OH solution in 4 Yellow ppt. Perform the flame test with a part of the solution and heat. If excess. A blue ppt., (ii) Perform boraxbead test with the salt. - Blue bead salt. ammonia gas evolves 2+ + suspended in a 2+ (i) Light green flame-Ba confirmed. Confirmation of Ni NH4 is present. colourless medium 2+ (called a lake) (ii) Crimson red flame-Sr confirmed. Pass the gas through (i) Take O.S. and make alkaline by adding NH4OH and then add a 2+ Nessler’s reagent. A few drops of dimethyl glyoxime - Bright red ppt. (iii) Brick red flame-Ca confirmed. brownish ppt. or (ii) Perform borax bead test with the salt - Brown bead in colouration is oxidising flame and grey bead in reducing flame. obtained. 2+ Confirmation of Mn + Note: NH4 may be (i) Dissolve flesh coloured ppt. in dil. HCl, boil off H2S, add NaOH tested in the beginning of analysis and Br2 water. - White ppt. turning grey. of basic radicals as (ii) Perform borax bead test with group ppt. - Pink bead in zero group. oxidising flame and colourless in reducing flame.