EXPERIMENT No. Aim: To detect the presence of one acidic and one basic radical in the given sample of salt (packet no.____) Preliminary Investigation Physical state: Solid Colour : White fine powder Odour : Ammonium smell ( NH4 + may be present) Solubility : Soluble in water Identification of Acidic Radical S.No. Procedure Observation Inference a) Preliminary test : 1 Salt was taken in a test tube, dilute H2SO4 was added to it No gas evolved CO32-, SO32-, S2-, NO2are absent 2 Salt was taken in a test tube, Conc. H2SO4 was added to it then heated and a glass rod dipped in NH4Cl is brought near the mouth of the test tube Colourless gas with pungent smell which gives dense white fumes of NH4Cl May be Cl- is present Confirmatory test for Cl- 1 2 Conc. HNO3 and AgNO3 solution was added in the salt solution Dissolved this ppt in NH4OH Chromyl chloride test: To the salt solid K2Cr2O7 and conc. H2SO4 was added and heated. The evolved vapours were passed through NaOH solution. To the yellow solution thus obtained, acetic acid and lead acetate solution was added Curdy white ppt. Cl- is confirmed White ppt. soluble in NH4OH A yellow solution obtained Chemical reaction involved in the confirmation of Chloride Preliminary test: 2NH4Cl + H2SO4 NH4OH + HCl Silver nitrate test Heat (NH4)2SO4 + 2HCl NH4Cl + H2O (white fumes) Cl- is confirmed AgCl ↓ + NaNO3 (white ppt) [Ag(NH3)2Cl]Cl. + 2H2O (Soluble complex) NaCl + AgNO3 AgCl + 2NH4OH Chromyl Chloride test: 4NaCl + K2Cr2O7 + 6H2SO4 4NaHSO4 + 2KHSO4 + 2CrO2Cl2 + 3H2O (Chromyl Chloride) CrO2Cl2 + 4NaOH Na2CrO4 + 2H2O + 2NaCl (Sod. Chromate) PbCrO4↓ + 2CH3COONa Na2CrO4 + (CH3COO)2Pb (Lead Chromate yellow ppt.) Identification of Basic Radical S.No. Procedure Observation Inference To the salt, NaOH solution is added and then heated. Ammonia gas evolves May be NH4+ is present A brownish ppt. obtained. NH4+ Confirmed 1 The gas passed through Nessler's reagent Chemical reaction involved in Group-Zero Analysis NH4Cl + NaOH Δ NH3 + HCl NaCl + H2O + NH3 ↑ NH4Cl White fumes Nessler’s reagent 2K2[HgI4] + NH3 + 3KOH Nessler’s reagent H2N.HgO.HgI ↓ + 7KI + 2H2O Brown ppt. Result: The acidic radical in the given salt sample is Cl- and the basic radical in the given salt sample is NH4+. EXPERIMENT No. Aim: To detect the presence of one acidic and one basic radical in the given sample of salt (packet no. ___) Preliminary Investigation Physical state: Solid Colour : White crystalline Odour : Vinegar smell Solubility : Soluble in water Identification of Acidic Radical S.No. Procedure Observation Inference a) Preliminary test : 1 A pinch of salt taken in a test tube, dilute H2SO4 was added to it. No gas evolved CO32-, SO32-, S2-, NO2are absent 2 A pinch of salt taken in a test tube, and heated with conc. H2SO4 Colourless gas with vinegar smell May be CH3COO- is present 1 Oxalic acid test: To the salt, Oxalic acid and 2-3 drops of water was added and rubbed. Vinegar smell produced CH3COO- is confirmed 2 Ester test: To the salt, Conc, H2SO4 and ethyl alcohol was added and heated. Pleasant fruity smell of ester CH3COO- is confirmed 3 Neutral Ferric Chloride test: To the salt solution, 1-2 ml of neutral ferric chloride solution ias added and boiled Deep red colour appears which disappears on boiling and a brown-red precipitate is formed CH3COO- is confirmed Confirmatory test for CH3COO- Chemical reaction involved in the confirmation of Acetate Oxalic acid test: COOH | COOH + 2CH3COONa + [O] K2SO4 + 2MnSO4 + 18H2O + 10CO2 Ester test: 2CH3COONa + H2SO4 CH3COOH + C2H2OH Na2SO4 + 2CH3COOH CH3COOC2H5 + H2O Etyhl Acetate (Fruity Smell) Neutral Ferric Chloride test: 6CH3COO- + 3Fe3+ + 2H2O [Fe3(OH)2(CH3COO)6]+ + 4H2O [Fe3(OH)2(CH3COO)6]+ + 2H+ 3[Fe3(OH)2(CH3COO)] + 3CH3COOH + H+ (Brown-red precipitate) Identification of Basic Radical _____________ S.No. Observation Inference To the Salt, NaOH solution was added and heated. No gas evolved Group Zero (NH4+) absent 2 To Salt , distilled water and dil HCl was added to it White Precipitate is formed First Group (Pb2+) is Present 3 The ppt. was boiled with distilled water and divided in to two parts (i) KI (potassium Iodide) was added to one part of the solution (ii) K2CrO4 was added to the second part of the solution 1 Procedure Yellow ppt. is formed Pb2+ is Confirmed Yellow ppt. is formed Chemical reaction involved in I Group Analysis Pb(NO3)2 + 2HCl PbCl2 ↓ + H2O + 2HNO3 ↑ White ppt Potassium Iodide test: PbCl2 + 2KI Potassium chromate test:PbCl2 + K2CrO4 PbI2↓ + 2KCl Yellow ppt PbCrO4↓ + 2KCl Yellow ppt Result: The acidic radical in the given salt sample is CH3COO- and the basic radical in the given salt sample is Pb2+. EXPERIMENT No.05 Aim: To detect the presence of one acidic and one basic radical in the given sample of salt (packet no. ____) Preliminary Investigation Physical state: Solid Colour : Transparent crystalline Odour : Odourless Solubility : Soluble in water Identification of Acidic Radical S.No. Procedure Observation Inference No gas evolved CO32-, SO32-, S2-, NO2are absent Reddish brown gas with pungent sell is evolved (turns FeSO4 sol. black) NO3- May be present a) Preliminary test : 1 A pinch of salt was taken in dry test tube and dil H2SO4 was added to it. 2 A pinch of salt was taken in dry test tube and conc. H2SO4 was added to it and heated. Confirmatory test for NO3 - 1 To the salt conc. H2SO4 and Cu chips were added and heated. Reddish brown gas evolved NO3- is confirmed 2 To Salt, FeSO4 solution was added and then conc. H2SO4 along the sides of test tube was added Dark brown ring is formed at the junction of two solutions NO3- is confirmed Chemical reaction involved in the confirmation of Nitrate KNO3 + H2SO4 HNO3 + C KHSO4 + HNO3 4NO2 + CO2 ↑ + 2H2O Paper pellet Copper test:2KNO3 + H2SO4 4HNO3 + Cu K2SO4 + 2NHO3 Cu(NO3)2 + 2NO2 + 2H2O (Reddish brown gas) Ring test:KNO3 + H2SO4 KHSO4 + HNO3 6FeSO4 + 3H2SO4 + 2NHO3 3Fe2(SO4)3 + 4H2O + 2NO FeSO4 + NO + H2O [Fe(NO)(H2O)5]SO4 Brown ring Identification of Basic Radical S.No. Procedure Observation Inference 1 A pinch of salt was taken in a test and NaOH solution was added ot it and heated the gas evolved was passed through Nessler’s reagent No Colouration obtained Group 0 (NH4+) is absent 2 A Pinch of salt was taken in a test tube, distilled water and dil. HCl was added to it. No ppt is formed Group 1 (Pb2+) is absent 3 Through the above obtained solution, H2S gas was passed. No ppt is formed Group II (Pb2+, Cu2+, As3+) , is absent 4 To the Original Solution, Solid NH4Cl, 0.5ml conc. HNO3 was added, boiled and then cooled. NH4OH was added in the solution. White ppt. obtained Al3+ may be present 5 Confirmation test: The ppt. obtained is dissloved dil HCl, blue litmus solution and NH4OH was added drop wise till blue colour developed. Blue ppt. floating in the colourles solution obtained Al3+ presence confirmed Chemical reaction involved in III Group Analysis AlCl3 + 3NH4OH 3NH4Cl + Al(OH)3 ↓ White ppt Lake test: Al(OH)3 + 3HCl AlCl3 + 3NH4OH AlCl3 + 3H2O 3NH4Cl + Al(OH)3↓ Blue colour adsorbs on this ppt Result: The acidic radical in the given salt sample is NO3- and the basic radical in the given salt sample is Al3+. EXPERIMENT No. Aim: To detect the presence of one acidic and one basic radical in the given sample of salt (packet no. ___) Preliminary Investigation Physical state: Solid Colour : Fine powder Odour : Odourless Solubility : Soluble in water Identification of Acidic Radical S.No. Procedure Observation Inference No gas evolved CO32-, SO32-, S2-, NO2are absent Colourless gas with pungent smell which gives dense white fumes of NH4Cl May be Cl- is present a) Preliminary test : 1 Salt was taken in a test tube, dilute H2SO4 was added to it 2 Salt was taken in a test tube, Conc. H2SO4 was added to it then heated and a glass rod dipped in NH4Cl was brought near its mouth. Confirmatory test for Cl- 1 2 Conc. HNO3 and AgNO3 solution was added in the salt solution Dissolved this ppt in NH4OH Chromyl chloride test: To the salt solid K2Cr2O7, conc. H2SO4 was added and heated. The evolved vapours were passed through NaOH solution. To the yellow solution thus obtained, Curdy white ppt. Cl- is confirmed White ppt. soluble in NH4OH A Yellow solution obtained Cl- is confirmed acetic acid and lead acetate solution was added Preliminary test: 2NH4Cl + H2SO4 NH4OH + HCl Silver nitrate test: NaCl + AgNO3 AgCl + 2NH4OH Heat (NH4)2SO4 + 2HCl NH4Cl + H2O (white fumes) AgCl ↓ + NaNO3 (white ppt) [Ag(NH3)2Cl]Cl. + 2H2O (Soluble complex) Chromyl Chloride test: 4NaCl + K2Cr2O7 + 6H2SO4 3H2O 4NaHSO4 + 2KHSO4 + 2CrO2Cl2 + (Chromyl Chloride) CrO2Cl2 + 4NaOH Na2CrO4 + 2H2O + 2NaCl (Sod. Chromate) Na2CrO4 + (CH3COO)2Pb PbCrO4↓ + 2CH3COONa (Lead Chromate yellow ppt.) Identification of Basic Radical S.No. Procedure Observation Inference 1 A pinch of salt was taken in a test and NaOH solution was added ot it and heated the gas evolved was passed through Nessler’s reagent No Colouration obtained Group 0 (NH4+) is absent No ppt is formed Group 1 (Pb2+) is absent No ppt is formed Group II (Pb2+, Cu2+, As3+) , is absent No ppt is formed Group III (Fe3+, Al3+) is absent 2 3 4 A Pinch of salt was taken in a test tube, distilled water and dil. HCl was added to it. Through the above obtained solution, H2S gas was passed. To the Original Solution, Solid NH4Cl, 0.5ml conc. HNO3 were added, boiled and then cooled. NH4OH was added in the solution. 5 Through the above obtained solution, H2S gas was passed. No ppt is formed Group IV (Zn2+, Co2+, Ni2+) is absent 6 To the original solution, solid NH4Cl, NH4OH and (NH4)2CO3 solution were added White ppt. is formed Group V (Sr2+) may be present 7 Confirmation test: Above obtained ppt. was dissolved in acetic acid and CO2 was boiled off. To one part of the solution K2CrO4 solution was added. 8 Second part of the ppt. ammonium sulphate solution was added To the salt, dil HCl was added and a paste was prepared this paste was taken on a platinum wire and tested on a flame Chemical reaction involved in V Group Analysis Ba2+ is absent No ppt is formed White ppt. is formed Crimson-Red flame Sr2+ presence confirmed Sr2+ presence confirmed SrCl2 + (NH4)2CO3 SrCO3 + 2CH3COOH (CH3COO)2Sr + (NH4)2SO4 SrCO3↓ + 2NH4Cl (CH3COO)2Sr + CO2 + H2O 2CH3COONH4 + SrSO4↓ White ppt Result: The acidic radical in the given salt sample is Cl- and the basic radical in the given salt sample is Sr2+. EXPERIMENT No.07 Aim: To detect the presence of one acidic and one basic radical in the given sample of salt (packet no. ____) Preliminary Investigation Physical state: Solid Colour : White Odour : Odourless Solubility : Soluble in water Identification of Acidic Radical S.No. Procedure Observation Inference No gas evolved CO32-, SO32-, S2-, NO2are absent a) Preliminary test : 1 Salt was taken in a test tube, dilute H2SO4 was added to it 2 A pinch of salt has been taken in dry test tube and conc. H2SO4 has been added to it and heated. No gas evolved Cl-, Br-, I-, NO3-, C2O42-, CH3COO- are absent 3 Barium chloride test: dil HCl and BaCl2 solution was added to aqueous salt solution A white ppt. insoluble in dil HCl was obtained Presence of SO42- Appearance of white ppt. Confirmed Presence of SO42- Confirmatory test for SO42- 4 The aqueous solution is acidified with acetic acid and lead acetate solution Chemical reaction involved in the confirmation of Sulphate Preliminary test: Na2SO4 + BaCl2 Na2SO4 + (CH3COO)2Pb BaSO4 ↓ + 2NaCl (white ppt) PbSO4 + 2CH3COONa Identification of Basic Radical S.No. Procedure Observation Inference 1 A pinch of salt was taken in a test and NaOH solution was added ot it and heated the gas evolved was passed through Nessler’s reagent No Colouration obtained Group 0 (NH4+) is absent 2 A Pinch of salt was taken in a test tube, distilled water and dil. HCl was added to it. No ppt is formed Group 1 (Pb2+) is absent 3 Through the above obtained solution, H2S gas was passed. No ppt is formed Group II (Pb2+, Cu2+, As3+) , is absent 4 To the Original Solution, Solid NH4Cl, 0.5ml conc. HNO3 were added, boiled and then cooled. NH4OH was added in the solution. No ppt is formed Group III (Fe3+, Al3+) is absent 5 Through the part of above solution, H2S gas was passed No ppt. is formed Group IV (Zn2+, Ni2+) is absent 6 To the original solution, solid NH4Cl, NH4OH and (NH4)2CO3 solutions were added No ppt. is formed Group V (Ba2+, Ca2+, Sr2+) is absent Confirmation test Mg2+: 7 To the Original solution, a pinch of NH4Cl and a few drops of NH4OH were added. Excess of Ammonium Phosphate solution added to it. White ppt. is formed Group VI (Mg2+) presence confirmed Chemical reaction involved in VI Group Analysis MgCl2 + NH4OH + (NH4)2HPO4 Mg(NH4)PO4↓ + 2NH4Cl + H2O (White ppt) Result: The acidic radical in the given salt sample is SO42- and the basic radical in the given salt sample is Mg2+.
