Match the List-I with List-II : Cations Group reaction P → Pb 2 + , Cu 2 + H 2 S gas in presence of dilute HCl Q → Al 3 + , Fe 3 + NH 4 2 CO 3 in presence of NH 4 OH R → Co 2 + , Ni 2 + NH 4 OH in presence of NH 4 CI S → Ba 2 + , Ca 2 + H 2 S in presence of NH 4 OH

Step-by-step solution

Group reagents for precipitating ions: Group Cations Group reagent Zero NH 4 + None I Pb 2 + Dilute HCl II Pb 2 + ,   Cu 2 + ,   As 3 + H 2   S gas in presence of dil. HCl III Al 3 + ,   Fe 3 + NH 4 OH in presence of NH 4 Cl IV Co 2 + ,   Ni 2 + ,   Mn 2 + ,   Zn 2 + H 2 S in presence of NH 4 OH V Ba 2 + ,   Sr 2 + ,   Ca 2 + ( NH 4 ) 2 CO 3 in presence of NH 4 OH VI Mg 2 + None So, the correct answer is P → i ,   Q → iii ,   R → iv ,   S