(Study Material) Salt Analysis of Cations and Anions (Chemistry)
Disclaimer: This website is NOT associated with CBSE, for official website of CBSE visit - www.cbse.gov.in
Salt Analysis
Cations
Group | Group Reagent | Radicals |
Zero Group | O.S. + NaOH + Heat | NH4+ |
I Group | O.S. + HCl | Pb2+ |
II Group | O.S. + HCI + H2S | Cu2+ |
III Group | O.S. +NH4Cl + NH4OH | AI2+ ,Fe3+ |
IV Group | O.S. + NH4CI + NH4OH +H2S |
Ni2+ ,Mn2+ , Zn2+ ,Co2+ |
V Group | O.S. + NH4CI + NH4OH +(NH4)2CO3 | Ba2+, Ca3+, Sr2+ |
VI Group | O.S + NH4CI + NH4OH + NaH2PO4 | Mg2+ |
Anions
Group | Group Reagent | Radicals |
I Group | Salt + dil. H2SO4 | CO32-, SO32-, S2-, NO2- |
II Group | Salt + conc. H2SO4 | Cl-, Br-, I-, CH3COO- |
|
Add Cu piece and heat | NO- |
|
Add KMnO4 soln. | c2o42- |
III Group | O.S. + BaC!2 | so42- |
IV Group | O.S + Conc.HNO3 + Heat + (NH4)24 MoO | PO43- |
Preliminary Tests
Test | Observation | Inference |
Physical Appearance | ||
Colour | White | NH4+, Pb2+, Al3+ , Zn2+, Ba2+, Ca2+ , Sr2+ and Mg2+ |
Blue | Cu2+ | |
Green | Ni2+ | |
Brown | Fe3+ | |
Red | Co2+ | |
Light pink | Mn2+ | |
Odour | Smell of NH3 | NH4+ |
Smell of vinegar | CH3COO- | |
Smell of rotten eggs | H2- | |
Dry Heating | Colourless gas evolved | CO32- , SO32-, S2- and Cl- |
Blown gas evolved | Br-, NO3- | |
Violet gas evolved | I- | |
Crackling sound | Pb(NO3)2 and Ba(NO3)2 | |
Brown residue | Cu2+ | |
Flame Test | Greenish blue | Cu2+ |
Light green | Ba2+ | |
Brick red | Ca2+ | |
Crimson red | Sr2+ |
Know more about: Simultaneous Cation and Anion Analysis with Charged Aerosol Detection