KCN is used for separating

Options

A. `CO^(+2)` and `Ni^(+2)`
B. `Mn^(+2)` and `Zn^(+2)`
C. `Ba^(+2)` and `Ca^(+2)`
D. `Cu^(+2)` and `Cd^(+2)`

Answer

A, D

Explanation

a) `Cd^(2+) overset(KCN+H_(2)S)to underset("yellow ppt")(CdS darr)" "`b) `Cu^(2+) overset(KCN)to K_(3) underset("soluble complex")([Cu[CN]_(4)])`
c) `Co^(2+)+2CN^(-) to Co^(2+) underset("Reddul brown ppt")([CN]_(2)darr)" "`d)` Ni^(+2)+2CN^(-) to underset("green ppt")(Ni(CN)_(2)darr)`