Systematic Analysis of Inorganic Simple Salt-Scheme PDF

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This document is a laboratory experiment related to inorganic chemistry, specifically focused on the analysis of inorganic salts. The procedure outlines various tests for identifying different ions and anions within the samples. The experiment involves observations and inferences.

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Systematic Analysis of Inorganic Simple Salt-Scheme A.Preliminary Examination Sl.No Experiment Observation Inference 1 Colour is noted May be presence of...

Systematic Analysis of Inorganic Simple Salt-Scheme A.Preliminary Examination Sl.No Experiment Observation Inference 1 Colour is noted May be presence of Cu2+ a)Blue Mn2+ b) Pink Absence of Cu2+,Mn2+ c)Colourless 2 Smell is noted a)Vinegar smell Maybe presence of CH3COO- Maybe presence of NH4+ b) Smell of ammonia 3. To a little of salt Clear solution Presence of NH4+. solution, sodium carbonate is added. 4. Action of heat a) Colourless gas with a)Presence of NH4+ smell of NH3 A little of the salt is heated strongly in a b)Yellow when hot and b) Presence of Zn2+ dry test tube white when cold c)Vapours with vinegar smell d)Colourless gas c) Presence of CH3COO- which turns lime water d) Presence of CO32- milky e) Presence of NO3- e)Reddish Brown vapours f)No Characteristic f) Absence of NH4+,Zn2+, Change CH3COO-,CO32-and NO3- 5. Flame Test a) Pale green flame a)Presence of Ba2+ A little of the solid b) Crimson red flame b) Presence of Sr2+ salt is made into a c) Brick red flame c)Presence of Ca2+ paste with very few drops of Conc. HCl in d) No characteristic flame d) Absence of Ba2+,Sr2+,Ca2+ a watch glass. The colouration mixture is introduced into flame with a glass rod. 6. Ash Test a) Blue tinted ash a)Presence of Al3+ b) Green tinted ash A little of the salt is c) Pink tinted ash b)Presence of Zn2+ boiled with about 3 d) No characteristic c)Presence of Mg2+ drops of Conc. HNO3, colour and a about 1 mL of d) Absence of Al3+,Zn2+,Mg2+ cobalt nitrate solution very strongly. A folded filter paper is dipped in the solution and burnt to ashes. Systematic analysis of Acid Radicals (Anions) 1 With dil. HCl Brisk effervescence with Presence of CO32- the evolution of colourless To a little of the salt, odourless gas 1ml. of dil. HCl is added. CO32-+2HCl 2 Cl-+H2O+CO2 (Brisk effervescence) 2 With dil. H2SO4 Vinegar smell Presence of CH3COO- A little of the salt is rubbed with dil.H2SO4 in a watch glass and smell is noted. CH3COO- +H2SO4 HSO4- + CH3COOH (Vinegar smell) 3 With Conc. H2SO4 A colourless fuming gas is Presence of Cl- evolved which produces A little of the solid dense white fumes when a salt is heated with glass rod dipped in about 1ml of Conc. NH4OH is shown into the H2SO4in a dry test gas. tube. Cl- +H2SO4 HSO4-+HCl (fuming gas) NH4OH + HCl NH4Cl + H2O (dense white fumes) 4 With Conc.H2SO4 Reddish brown vapours Presence of NO3- and Cu turnings and the solution turns blue A little of the solid salt is heated with 1ml of Conc.H2SO4.Add few copper turnings to it. NO3- + H2SO4 HNO3 + HSO4- Cu + 4HNO3 Cu(NO3)2 +2NO2+H2O (blue) (Reddish brown vapours) 5 With BaCl2 A thick white precipitate Presence of SO42- insoluble in dil. HCl To a little of the salt solution a little of BaCl2 is added and shaken well. SO42- + BaCl2 BaSO4 + 2 Cl- (white precipitate) Confirmatory tests for Acid Radicals 1 Carbonate Lime water turns milky CO32- confirmed. a)The gas obtained is passed through freshly prepared lime water. Ca(OH)2 + CO2 CaCO3+H2O (milky) b)To a little of the White Precipitate CO32- confirmed. salt solution a little of BaCl2 is added and shaken well. CO32- + BaCl2 BaCO3 + CaCl2 (White Precipitate) 2 Acetate A deep red coloration is CH3COO-confirmed. obtained. a)To one spatula of the solid salt 1ml. neutral FeCl3 solution is added. 3CH3COO-+FeCl3 (CH3COO)3 Fe +3Cl- (deep red) b) A little of the Pleasant Fruity smell CH3COO-confirmed. given salt solution is heated with 1ml of Conc.H2SO4 and 1ml of ethyl alcohol in a dry test tube and contents are poured into beaker containing Na2CO3 solution. CH3COO- + H2SO4 + C2H5OH CH3COOC2H5+H2O + HSO4- (fruity smell) 3 Chloride Curdy white precipitate Cl- confirmed. completely soluble in a)To a little of the NH4OH salt solution, dil HNO3 and AgNO3 solution are added. Cl- + AgNO3 AgCl + NO3- (curdy precipitate) AgCl+2NH4OH [Ag(NH3)2]Cl + H2O (soluble complex) b) One spatula of the A greenish yellow gas Cl- confirmed. solid salt is heated with a pungent smell. with a pinch of MnO2 and 3 drops of Conc. H2SO4 Cl- + MnO2 + H2SO4 HSO4- + MnSO4 + Cl2 (greenish yellow gas) 4 Nitrate A brown ring is obtained NO3- confirmed. at the junction of two a)Brown Ring lest- liquids. To a little of the salt solution equal amount of freshly- prepared FeSO4 solution is added and shaken well. Conc. H2SO4 is added to this carefully along the sides of the test tube. NO3- + Fe2++ 4H+ NO + Fe3+ + 2H2O [Fe(H2O)6]SO4 + NO [Fe(H2O)5NO]SO4 + H2O (Brown ring) b) A solution of Deep blue colouration NO3- confirmed. diphenylamine and sulphuric acid is added to salt solution. 2(C6H5)2NH + 2NO3 -+ H2SO4 SO4 2-+ 2H2O + 4(C6H5)NO (Deep blue) 5 Sulphate A thick white precipitate SO42- confirmed. a) a little of the salt solution 1ml of lead acetate solution is added. SO42-+(CH3COO)2Pb PbSO4 + 2CH3COO- (white precipitate) b) The above Soluble SO42- confirmed. precipitate is separated and to very less amount of precipitate ammonium acetate solution is added. PbSO4 + CH3COONH4 (CH3COO)2Pb + (NH4)2 SO4 (Soluble) Report :- Anion present in the given salt is -------------------- Systematic analysis of Basic radicals( Cations) 1 Group 0 (NH4+) Colourless gas with Presence of NH4+ pungent smell which gives Group reagent - dense white fumes when a NaOH glass rod dipped in dil. A little of the salt HCl is shown solution is heated with NaOH NH4+ + NaOH Na+ + H2O +NH3 (pungent smell) NH3 + HCl NH4Cl (dense fumes) 2 Group I (Pb2+) A heavy white precipitate Presence of Pb2+ is formed. Group reagent – dil.HCl To a little of the salt solution,1ml of dil. HCI is added Pb2+ + 2 Cl- PbCl2 (heavy white precipitate) 3. Group II (Cu2+) Black precipitate Presence of Cu2+ Group reagent – dil.HCl and H2S H2S is passed through the above solution Cu2+ + S2- CuS (black precipitate) 4. Group III (Al3+) A white gelatinous Presence of Al3+ precipitate is formed Group reagent – saturated NH4Cl and excess NH4OH The salt solution is mixed with saturated NH4CI solution and excess NH4OH solution is added in drops. Al3+ + 3OH- Al(OH)3 (gelatinous white precipitate) 5 Group IV (Zn2+/ Mn2+ ) Group reagent – saturated NH4Cl excess NH4OH and H2S The solution obtained in group III is divided into 3 a)A dirty white precipitate Presence of Zn2+ parts is formed a)To the first portion Zn2+ + S2- ZnS of the solution (dirty white obtained in group III, precipitate) H2S is passed. Presence of Mn2+ b) Flesh coloured precipitate is formed Mn2+ + S2- MnS (flesh coloured precipitate) 6 Group V (Ba2+/ Sr2+/ Ca2+) Group reagent – saturated NH4Cl excess NH4OH and (NH4)2CO3 b) To the second White Precipitate Presence of portion of the Ba2+/ Sr2+/ Ca2+ solution from group III, 1ml of Ba2+ + CO32- (NH4)2CO3 is added BaCO3 and shaken. (White Precipitate) Sr2++ CO32- SrCO3 (White Precipitate) Ca2++ CO32- CaCO3 (White Precipitate) 7 Group VI (Mg2+) Group reagent – saturated NH4Cl excess NH4OH and Na2HPO4 c) To the third portion of the Presence of solution from group III, 1ml of Na2HPO4 White precipitate Mg2+ is added and shaken. Mg2++Na2HPO4 +NH4OH→Mg(NH4)PO4+Na++H2O (White Precipitate) Confirmatory Tests for Basic Radicals 1 NH4+ a)Little of the salt Clear Solution Presence of NH4+ solution is treated with Na2CO3 solution. Na2CO3 + NH4+ → Na++ (NH4)2CO3 (White Precipitate) b) To about 1 ml of A brown precipitate is NH4+ confirmed. salt solution Nessler’s formed reagent is added NH4+ +KOH NH3+K++ H2O 2K2HgI4 + NH3 + 3KOH → NH2.HgO.HgI + 7KI + 2H2O (Brown precipitate) 2 Pb2+ Pb2+ confirmed. The precipitate of group I is separated boiled with water and cooled and divided into 2 parts a) To the first portion of the above solution potassium chromate yellow precipitate is solution is added formed Pb2++ K2CrO4 PbCrO4 + 2K+ (yellow precipitate) b) To the second A yellow precipitate Pb2+ confirmed. portion Potassium soluble in hot water and iodide solution is reappears as golden added yellow spangles on cooling. Pb2+ +2KI PbI2 + 2K+ (yellow precipitate) 3 Al3+ Al3+ confirmed. a)To the salt solution white precipitate is NaOH solution is formed which dissolves in added drop by drop in excess of NaOH solution excess AI3++3NaOH AI(OH)3+3Na+ (white precipitate) AI(OH)3+3NaOH NaAIO2+3H2O (soluble sodium aluminate) b)Ash Test Al3+ confirmed. A little of the salt is Blue tinted ash boiled with about I ml of Conc. HNO3, and a few drops of cobalt nitrate solution very strongly. A folded filter paper is dipped in the solution and burnt to ashes. 2 AI3+ HNO3 Al2O3 [O] 2 Al2O3 + Co(NO3)2 2 CoO. Al2O3 + 4NO2 + O2 (Blue tinted ash) (double oxide of cobalt and aluminium) 4 Zn2+ white precipitate is Zn2+ confirmed. formed which dissolves in a)To the salt solution excess of NaOH solution NaOH solution is added drop by drop in excess Zn2++2NaOH Zn(OH)2+2Na+ (white precipitate) Zn(OH)2+2NaOH Na2ZnO2+2H2O (soluble sodium zincate) b)Ash Test Green tinted ash Zn2+ confirmed. A little of the salt is boiled with about 1ml of Conc. HNO3, and a few drops of cobalt nitrate solution very strongly. A folded filter paper is dipped in the solution and burnt to ashes. Zn2+ HNO3 ZnO [O] 2 ZnO + Co(NO3)2 2 CoO. ZnO + 4NO2 + O2 (Green tinted ash) (double oxide of cobalt and zinc) 5 Mn2+ a)To a little of the A white precipitate turns Mn2+ confirmed salt solution NaOH brown on standing solution is added drop by drop in excess Mn2+ +2NaOH Mn(OH)2+2Na+ Mn(OH)2 + O2 2MnO(OH)2 (brown precipitate) b) Little of salt Supernatant liquid is solution is boiled coloured purple. Mn2+ confirmed with about 1ml of Conc. HNO3 and two spatula of lead dioxide. The mixture is heated strongly, cooled, diluted with water and allowed to stand. Mn2+ + PbO2 + 6HNO3 5 Pb2+ + 2HMnO4 + 2H2O (purple) 6 Ba2+ The group V precipitate is dissolved in minimum amount of acetic acid and CO2 is boiled off. The solution is divided into 3 portions a) To the first part of Yellow precipitate Ba2+ confirmed. solution, 1 ml of potassium chromate is added Ba2++ K2CrO4 BaCrO4 + 2K+ (yellow precipitate) b)Flame Test A pale green flame Ba2+ confirmed. A little of the solid salt is made into a paste with very few drops of Conc. HCl in a watch glass. The mixture is introduced into flame with a glass rod. 7 Sr2+ White precipitate Sr2+ confirmed. a)To the second part of the solution,(NH4)2SO4 solution is added and warmed. Sr2+ + (NH4)2SO4 SrSO4 + 2NH4+ (White precipitate ) b)Flame Test Crimson red flame Sr2+ confirmed. A little of the solid salt is made into a paste with very few drops of Conc. HCl in a watch glass. The mixture is introduced into flame with a glass rod. 8 Ca2+ White precipitate Ca2+ confirmed. To the third part of the solution,(NH4)2C2O4 is added. Ca2+ + (NH4)2C2O4 CaC2O4 + 2NH4+ (White precipitate) b)Flame Test Brick red flame Ca2+ confirmed. A little of the solid salt is made into a paste with very few drops of Conc. HCl in a watch glass. The mixture is introduced into flame with a glass rod. 9 Mg2+ Pink tinted ash Mg2+ confirmed. a)Ash Test A little of the salt is boiled with about 1ml of Conc. HNO3, and a few drops of cobalt nitrate solution very strongly. A folded filter paper is dipped in the solution and burnt to ashes. Mg2+ HNO3 MgO [O] 2 MgO + Co(NO3)2 2 CoO. MgO + 4NO2 + O2 (pink tinted ash) (double oxide of cobalt and magnesium) b)To a little of the Blue colouration Mg2+ confirmed. salt solution a few drops of NaOH solution and a few drops of Magneson reagent is added Result:- Basic radical present in the given salt is -------------------- Overall Report The given inorganic simple salt is --------------------------------

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