Cations Flashcards
1
Q
Groups:
A
- dil HCl
- H2S in dil HCl
a. InSoluble in yellow ammonium sulphide
b. Soluble in Yellow Ammonium Sulphide - NH4OH in NH4Cl
- H2S in NH3 and NH4Cl
- (NH4)2CO3 in NH4Cl and NH4OH
- No common
2
Q
- dil HCl
A
Pb2+ (PbCl2 -> Soluble in Hot water)
Hg+
Ag+
3
Q
2a. H2S in dil HCl
Insoluble in yellow ammonium sulphide
A
Hg2+
Cu2+
Cd2+
Bi3+
Pb2+
Ppt in both acidic and basic medium
lower ksp
4
Q
2b. H2S in dil HCl
Soluble in Yellow Ammonium Sulphide
A
As3+
As5+
Sb3+
Sb5+
Sn2+
Sn4+
ppt in both acidic/basic medium
5
Q
- NH4OH in NH4Cl
A
Fe3+
Al3+
Cr3+
6
Q
- H2S in NH3 and NH4Cl
A
Ni2+
Co2+
Mn2+
Zn2+
Only Basic Medium Ppt
7
Q
- (NH4)2CO3 in NH4Cl and NH4OH
A
Ba2+
Sr2+
Ca2+
White Precipitate. Insoluble in water
8
Q
- No common group re-agent
A
Mg2+
Na+
K+
NH4+ –> Na2HPO4
9
Q
- NH4+
A
Liberates ammonia with NaOH, KOH
Not Mg(OH)2 -> Insoluble in water
10
Q
- i) Pb2+ tests (Acid and Bases)
A
- White ppt with dil. HCl -> Soluble in hot water and conc HCl
- Insoluble Ph(OH2) with NH4OH
- Soluble Pb(OH)2 with NaOH
-> Oxidised to PbO2 with H2O2 and Na2S2O8
11
Q
- i) Pb2+ Tests (Other re-agents)
A
- K2CrO4
- KI
- KCN
12
Q
A