Quantitative Analysis of SaltsInference from the colour of salt solutionsCationCu2+Fe2+Fe3+

Colour of solutionBlueGreenBrown

Test for GasesName of gasColour of gasSmell of gasEffect on damp litmusConfirmation test on gas

OxygenColourlessNo smellNo effectRekindles a glowing wooden splint

HydrogenColourlessNo smellNo effectProduce pop sound with a lighted wooden splint

Carbon dioxideColourlessNo smellDamp blue litmus turns to redLime water turn milky

AmmoniaColourlessPungentDamp red litmus turn blueForms white fume with concentrated HCI vapour

ChlorineGreenish-yellowChokingDamp blue litmus turns red-

Hydrogen ChlorideColourlessPungentDamp blue litmus turns redForms white fumes with concentrated NH3 vapour

Sulphur dioxideColourlessPungentDamp blue litmus turns redDecolourises purple colour of acidified potassium manganate(VII) solution

Nitrogen dioxideBrownPungentDamp blue litmus turns red-

Test of Anion in Aqueous Solution1) Test for carbonate ions, CO32- When dilute acid is added to an aqueous carbonate solution, effervescence occurs The gas evolves turn lime water milky. CO2 is produced2) Test for nitrate ions, NO3- (brown ring test) When dilute sulphuric acid and iron(II) sulphate solution are added to an aqueous nitrate solution, followed by concentrated sulphuric acid slow along the side of the test tube, a brown ring is formed in the middle section of the solution mixture. The formation of the brown ring (a complex) indicates the presence of nitrate ions.3) Test for sulphate ions, SO42- When a dilute hydrochloric acid is added to an aqueous sulphate solution followed by barium chloride solution, a white ppt (BaSO4) is formed. BaCI2 solution provide the Ba2+ ions to react with the SO42- ions.4) Test for chloride ions, CI- When dilute nitric acid is added to an aqueous chloride solution followed by silver nitrate solution, AgNO3, a white ppt (AgCI) is formed. Test of CationsReagentObservationInference

Add NaOH in excessWhite ppt solubleZn2+/Al3+/Pb2+

White ppt insolubeCa2+/Mg2+

Add NH3 in excessWhite ppt solubleZn2+

White ppt insolubleAl3+/Pb2+/Mg2+

Add NaOH and NH3 in excessGreen ppt insoluble in NaOH and NH3Fe2+

Brown ppt insoluble in NaOH and NH3Fe3+

Add NaOH in excessAdd NH3 in excessBlue ppt insoluble in NaOH but soluble in NH3 to form dark blue colorCu2+

No ppt form, but NH3 gas evolves when heatedNH4+

Confirmatory test for Fe2+, Fe3+, and Pb2+ ionsCationsSpecific reagentObservation

Pb2+KI, NaIYellow ppt, soluble in hot water

NH4+Nessler reagentBrown ppt

Fe2+Potassium hexacynoferrate (II), K4Fe(CN)6Light blue ppt

Potassium hexacynoferrate (III), K3Fe(CN)6Dark blue ppt

Fe3+Pottasium thiocynate, KSCNBlood red colour

K4Fe(CN)6Dark blue ppt

K3Fe(CN)6Greenish-brown sol