[INORGANIC CHEMISTRY] Inorganic Qualitative Analysis Summary

MercuLeS

Group I: Mercury, Lead, Silver

Group I

The insoluble chlorides

precipitant of insoluble chlorides

6M HCl

Ag + HCl

AgCl = white curdy precipitate

Pb + HCl

PbCl2 = white precipitate

Hg + HCl

Hg2Cl2 = white precipitate

Copper-CaBLe MArTiAn

Group II: Copper, Cadmium, Bismuth, Lead, Mercuric, Arsenic, Tin, Antimony

precipitant of Group II

5% thioacetamide in diluted acid

Group II

The acid insoluble sulfides

Group II A cations

Copper, Cadmium, Bismuth, Lead

insoluble in sodium sulfide (Na2S)

Group IIA

Group IIB cations

Mercuric, Arsenic, Tin, Antimony

soluble in sodium sulfide (Na2S)

Group IIB

NiCo ZaCh Iron Man

Group III: Nickel, Cobalt, Zinc, Chromium, Iron, Manganese

precipitant of group III

5% thioacetamide in ammonia (NH4)

Group III

The base insoluble sulfides

Group IIIA cations

Nickel, Cobalt

soluble in 1M HCl

Group IIIA

insoluble in 1M HCl

Group IIIB

Cd2+

Sn2+ (brown)

As2+

As5+

Yellow precipitated sulfides

Sb2+

Sb5+ (red-orange)

Orange precipitated sulfides

Zn2+

White precipitated sulfide

Mn2+

Pink precipitated sulfide

Cu2+

Bi3+

Pb2+

Sn4+

Hg2+

Co2+

Ni2+

Ag+

Fe2+

Black precipitated sulfide

BaCal St

Group IV: Barium, Calcium, Strontium

precipitant of group IV

Ammonium carbonate (NH4)2CO3 + 95% ethanol

Group IV

The soluble sulfides

The insoluble carbonates

Group IV precipitates

All are white precipitates

PoLiS Magnum Ammo

Group V: Potassium, Lithium, Sodium, Magnesium, Ammonium

precipitant for group V

None

Group V

The soluble group

yield colorless solution for all major identification test reagents

Group V

confirmatory reagent for group I

HCl + Ammonium hydroxide

white curdy precipitate with HCl, soluble in NH4OH

Ag+

white precipitate with HCl, insoluble in NH4OH

Pb+2

confirmatory reagent for group II

Potassium ferrocyanide

copper + potassium ferrocyanide

Brownish red precipitate

bismuth + potassium ferrocyanide

Yellowish white precipitate

confirmatory reagent for group III

Dimethylglyoxime (DMG)

zinc + DMG

Colorless urine

nickel + DMG

Cherry red precipitate

cobalt + DMG

Orange solution

confirmatory reagent for group IV

Saturated calcium sulfate (CaSO4)

calcium + saturated CaSO4

White precipitate

strontium + saturated CaSO4

Colorless solution

confirmatory reagent for group 5

Diluted NaOH

potassium + diluted NaOH

Odorless

ammonium + diluted NaOH

Pungent odor

preliminary examination: blue salts

Copper

preliminary examination: green

Ni+2

Ferrous (Fe+2)

Chromic (Cr+3)

Manganates

preliminary examination: yellow

Chromate

Ferric ion (Fe+3)

preliminary examination: red-orange

Dichromate ion

preliminary examination: purple

Permanganate

preliminary examination: pink

Mn+2

Cobaltous (Co+2)

an analytical method used for detecting the presence of certain metals where a small amount of a substance is volatilized and the characteristic glow of the substance is observed

Flame test

luminous flame

Yellow

non luminous flame; where the flame test is conducted

Blue flame

Parts of flame

(Top to bottom)

Upper oxidizing zone

Upper reducing zone

Hottest portion of the flame

Lower oxidizing zone

Lower reducing zone

Lower temperature zone

hottest portion of the flame; where the flame test is conducted

1/3 height of the flame

persistent golden yellow in normal flame test

Na

violet (lilac) in normal flame test

K

Carmine red in normal flame test

Lithium

Crimson red in normal flame test

Strontium

brick red in normal flame test

Calcium

yellowish green in normal flame test

Barium

green in normal flame test

Borates, Thallium, Copper

blue (wire slowly corroded) in normal flame test

Lead, Arsenic, Bismuth, Antimony, Copper

done using platinum wire dipped in conc HCL over non-luminous bunsen flame

the cobalt glass absorbs radiation form Na

Flame test with cobalt glass

Na in flame test with cobalt glass

Nil

K in flame test with cobalt glass

Crimson red

Ca in flame test with cobalt glass

Light green

Sr in flame test with cobalt glass

Purple

Barium in flame test with cobalt glass

Bluish green