The correct option(s) to distinguish nitrate salts of `Mn_(2)+ and Cu_(2)` + taken separately is(are)

Options

A. `Mn^(2+)` shows the characteristic green colour in the flame test
B. Only `Cu^(2+)` shows the formation of precipitate by passing `H_(2)S` in acidic medium
C. Only `Mn^(2+)` shows the formation of precipitate by passing `H_(2)S` in faintly basic medium
D. `Cu^(2+)//Cu` has higher reduction potential than `Mn^(2+)//Mnb` (measured under similar conditions)

Answer

B, D

Explanation

(a) `Cu^(+2) and Mn^(+2)` both gives green colour in flame test and cannot distinguished.
(b) `Cu^(+2)` belongs to group - II of cationic radical will gives ppt. of CuS in acidic medium.
(c) `Cu^(+2)` and `Mn^(+2)` both form ppt. in basic medium.
(d) `Cu^(+2)//Cu=+0.34V(SRP)`
`Mn^(+2)//Mn=-1.18V(SRP)`