Chemical Analysis of Salts: Anions and Cations

Classified in Chemistry

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Preliminary Test

Color of the Salt


Absence of Cu 2+, Fe 2+, etc

Odour of the Salt

Ammoniacal smell

Vinegar smell


Acetate ion


In water with no precipitate with Na2CO3

In dil HCl, soluble


No Group 1 cations

Salt is heated in a dry test tube

Colorless gas turns milky

Reddish brown fumes

Smell of ammonia

Pleasant smell


Nitrate ion


Acetate ion

Flame Test

Pale green

Brick red



Ash Test

Blue ash


Systematic Analysis for Anions

Dil HCl is added to a little of the saltBrisk effervescence of a colorless gasCO3
Salt is rubbed with dil H2SO4 in a watch glassVinegar smellAcetate
Salt is heated with conc H2SO4Colorless pungent smelling gas is evolved and dense white fumes are produced when a glass rod dipped in NH4OH is shown near the mouth of the test tubeChloride
Salt is heated with conc. H2S4Reddish brown vaporsNitrate
Salt is acidified with dil HCl and BaCl2White pptSulphate

Systematic Analysis for Cations

To aq salt soln, sodium carbonate sol is addedNo pptAmmonium
Dil HCl is added to a little of the salt solutionWhite pptLead
Solid NH4Cl added to salt solution of NH4OHWhite gelatinous pptAl
Solid NH4Cl is added to salt and then NH4OH and (NH4)2CO3 addedWhite pptBa or Ca

Confirmatory Test for Anion


The above gas is passed through lime water

Lime water turns milky

Few drops of BaCl2 solution is added

White ppt


Acidified with dil HNO3 and drops of silver nitrate

White ppt soluble in NH4OH

Salt is heated with manganese dioxide and conc sulphuric acid

Greenish yellow gas


Salt is warmed with conc H2SO4 and ethyl alcohol then poured excess water taken in beaker

Fruity smell

To salt soln, neutral ferric chloride solution is added

Red color formed


Freshly prepared ferrous sulphate soln is added to a little of the salt soln and then conc. H2SO4 is added along the sides of the test tube

Brown ring is formed at the junction of the solution

Salt solution acetic acid and lead acetate are added

Blue coloration

Ti salt soln acetic acid and lead acetate soln are addedWhite ppt
Excess ammonium actate soln is added to the above pptPpt is dissolved

Confirmatory for Cations

Ammonium ion
To salt soln NaOH soln is added and then Nessler's reagentReddish brown ppt
Salt soln is heated with NaOH solnSmell of ammonia and dense white fumes are produced when a glass rod is brought near the mouth of the test tube
Group III ppt is dissolved in dil HCl and added 2 drops of litmus soln. To this added NH4OH drop wiseBlue ppt floating the colorless solution
Salt is dissolved in 2 drops of conc HNO3 and boiled with a few drops of cobalt nitrate soln. A filter paper soaked in this soln is burnt to ashesBlue ash
A little acetic acid and potassium chromate solution are added to a little of salt solnYellow ppt
Flame test

Pale green color is imparted to the flame

To salt soln ammonium chloride, NH4 hydroxide and NH4 oxalate solutions are addedWhite crystalline ppt
Flame testBrick red color is imparted to the flame

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