Basic Radicals

1. Pb2+

1.1. salt and NaOH -> No NH3 gas-> zero gp. absent

1.2. aq. soln and dil HCl -> white ppt -> 1 gp. present (Pb2+ poss.)

1.3. aq ext. add KI soln -> Yellow ppt of PbCH3COO -> Pb2+ confirm

1.4. aq. ext add K2CrO4 -> yellow ppt of lead chromate -> Pb2+ confirm

2. Ba2+

2.1. salt and naoh -> no gas -> zero group absent

2.2. aq ext add dil HCl -> no ppt -> 1 gp. absent

2.3. above soln add h2s gas -> no ppt -> 2 gp. absent

2.4. boil above soln add conc. hno3 and nh4cl and nh4oh ->no ppt-> 3 gp. absent

2.5. pass h2s gas -> no ppt -> fourth gp. absent

2.6. add ammonium carbonate -> white ppt -> 5 present(Ba2+)

2.7. filter ppt and dissolove in HCl and add k2cro4 soln -> yellow ppt of barium chromate -> ba2+ conf.

3. NH4+

3.1. Pinch of salt in TT and add NaOH->Ammonical Smell -> Zero Group Present NH4+ Possible

3.2. Bring glass rod dipped in dil HCl over mouth -> White Fumes -> NH4+ possible

3.3. Filter paper dipped in Nesslers Reagent over mouth -> Brown filter paper -> NH4+ confirmed

4. Al3+

4.1. Pinch of salt and NaOH -> No NH3 gas -> Zero gp. absent

4.2. Aq Salt,and dil HCl -> No ppt -> 1 gp. absent(Pb2+)

4.3. Pass H2S gas -> No ppt -> 2 Gp. absent

4.4. expel h2s gas,add conc. HNO3 and NH4Cl and NH4OH -> White gellatine ppt -> 3 gp. present(Al3+ possible)

4.5. Filter ppt and add dil HCl , blue litmus soln and NH4OH dropwise -> Blue litmus soln floats -> Al3+ confirm