Question

Ibn the cyanide extraction process of silver form aragetite are ,oxidizing and reduction agents used are action .
A. `O_2` and `CO_2`
B. `O_2` and Zn dust
C. `HNO_3` and `CO`
D. `HNO_3` and Zn dust

Answer 1

Correct Answer - B
In the extraction of silver, `Ag_2S` is reached with `KCN` in the presence of air.
`2Ag_2S+8CN^(ɵ)+O_2+2H_2Oto4[Ag(CN)_2]^(ɵ)+2S+2OH`
(thus `O_2` is oxidant)
`2[Ag(CN)_2]^(ɵ)+Znto[Zn(CN)_4]^(2-)+2Ag(darr)` (Thus Zn is reductant)