AIM: Analyse systematically the given salt of inorganic compounds for anion and cation (by dry and wet test).
Test for Acidic Radicals
|
S.No. |
Treatment |
Observation |
Inference |
|
1 |
Mixture + dil. H2SO4 + Heat |
No reaction |
Week acidic group absent |
|
2 |
Mixture + conc. H2SO4 + Heat |
No reaction |
Strong acidic group absent |
|
3 |
Sodium coabonate extract + dil. HCl + BaCl2 solution |
White ppt. is formed |
SO42- May be present |
|
Confirmatory test : Dessolved tha above ppt in conc. HCl / conc. HNO3 |
Ppt is insoluble |
SO42- confirmed |
Test for Basic Radicals
|
S.No. |
Treatment |
Observation |
Inference |
|
1 |
Mixture + NaOH solution + Heat |
No ammonia smell |
Zero group Absent |
|
2 |
Original solution of Mixture + dil HCl |
No ppt. is formed |
1st group absent |
|
3 |
Pass H2S gas in above solution |
No ppt. is formed |
2nd group absent |
|
4 |
Boil the above solution off H2S gas | ||
|
Bring a filter paper dipped in lead acetate solution |
Filter paper not turn black |
H2S gas excaped | |
|
5 |
The above solution+ conc. HNO3+ boil + cool + solid NH4Cl + NH4OH in excess |
Red brown ppt. is formed |
3rd group present Fe3+ may be present |
|
6 |
Confirmatory test : Dissolve the above ppt. in dil. HCl and divide it into two parts 1st part + K4[Fe(CN)6] 2nd part + KCNS |
Prussian blue colour solution obtained Dark red colour solution obtained |
Fe3+ confirmed Fe3+ confirmed |
|
7 |
Dry test (Borax bead test) Past the borax powder on Pt wire and ignite it then touch the bead to ppt and again ignite it |
Yellow-green bead obtained |
Fe3+ confirmed |
Result : The above given salt contains anions SO42- and cations Fe3+ are present.