Inorganic Qualitative Analysis
acid radicals or (anions)
1) Solid salt + dil. HCl:
Observation
Effervescence and a colourless odouless gas is evolved.
The anion is carbonate or bicarbonate .
1 )Salt solution + magnesium sulphate solution
White precipitate
carbonate
No ppt
bicarbonate
Pungent brown fumes are evolved.
The anion is Nitrite
Colourless gas with Pungent odour
The anion is sulphite
yellow precipitate
The anion is thiosulphate.
paper black
The anion is sulphide
-ve
(Go to step 2).
2) Solid salt + conc. H2SO4:
Observation
colourless gas
The anion is chloride.
Raddish fumes
The anion is Bromide.
Violet fumes are evolved, and a brown or black
The anion is iodide.
-ve
If a small piece of copper metal and drops of water are added, dense brown fumes
Tha anion is Nitrate
-ve
(Go to step 3).
3) Salt solution + BaCl2:
Observation
white precipitate
Salt solution +AgNO3
yellow precipitate
phosphate
white ppt
which give brown ppt. after boiling
borate.
white ppt
sulphate
basic radicals or( cations)
Group I: Dilute Hydrochloric Acid Group
Salt solution + dil. Hydrochloric acid
** White ppt ** Salt solution + potassium chromate solution (K2CrO4))
brick red ppt
Silver Ag+
A yellow ppt.
Lead Pb++
brown ppt
Mercury (I)
Mercurous Hg22+
-ve
go step 2
Group II: Acid Sulphide Group
***Sub-group II-A***Salt solution +dil. HCl + hydrogen Sulphide solution (H2S)
canary yellow
Cadmium Cd++
black ppt
Copper Cu++
a brown ppt
Bismuth Bi+++
white ppt
Mercury(II),Mercuric Hg++
Salt solution + (solid) (NH4Cl) +
(NH4OH) + solution(H2S)
Gives a white ppt
Zinc Zn+2
Gives a buff ppt
Manganese Mn+2
Gives a black ppt.
Cobalt Co+2
Gives a black ppt
Nickel Ni+2
-ve
go to step 5
***Sub Group II – B***Salt Solution +
dil . HC1 +
hydrogen Sulphide Solution (H2S )
orang red ppt
Antimony Sb +++
a brown ppt
Tin ( II )
Stannous Sn ++
yellow ppt
Tin ( IV )
Stannics Sn ++++
-ve
go step 3
Group III: Ammonium Hydroxide Group
white gelatinous
Aluminum Al+3
grayish green
Chromium Cr+3
dirty green precipitate
Iron(II), Ferrous,Fe+2
reddish brown gelatinous ppt
Iron(III), Ferric ,Fe+3
-ve
go to step 4
Group Iv: Ammonium Sulphide Group
Group V : Ammonium Carbonate Group
Salt Solution + NH4Cl solid + NH4OH solution + (NH4)2CO3
Gives white ppt,Flame test
a brick red
Calcium Ca2+
a crimson red
Strontium Sr2+
green colour
Barium Ba2+
-ve
go to step 6
Group VI
They have no common reagent
Salt solution + Sodium hydroxide solution (NaOH):
Ammonium(NH4+)
Salt solution + Sodium hydroxide solution (NaOH):
Magnesium(Mg+)
Magnesium(Mg+)
Potassium (K+)
Flame test:
a golden yellow
Sodium (Na+)