Statement-1:In cyanide process for the extraction of gold and silver from their native ores, the cyanide solution acts as a reducing agent to reduce t
Statement-1:In cyanide process for the extraction of gold and silver from their native ores, the cyanide solution acts as a reducing agent to reduce the gold and silver compounds present in the ores, the cyanide solution acts as a reducing agent to reduce the gold and silver compounds present in the ores into the metallic states.
Statement-2:In the extraction of gold and silver the cyanide solution acts as complexing reagent in the presence of air and form their respective soluble complexes.
A. Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-1
B. Statement-1 is True, Statement-2 is True, Statement-2 is NOT a correct explanation for Statement-1
C. Statement-1 is True, Statement-2 is False.
D. Statement-1 is False, Statement-2 is True.
1 Answers
Correct Answer - D
Statement -1 : 4M(s)+`8CN^(-)(aq)+O_2(g)to overset(+I)(4[M(CN)_2]^(-)(aq)+4OH^(-)(aq).` M=Au or Ag. As it is clear from the equation that `CN^(-)` does not acts as reducing agent However `O_2` oxidies metal to metal ion which then react with `CN^(-)` ion to form complex from which metal is obtained by reduction by more electropositive metal, zinc,.
Statement-2:`4M(s)+8CN^(-)(aq.)+2H_2O(aq)+O_2(g)to overset(+I)(4[M(CN)_2]^(-)(aq)+4OH^(-)(aq).` M=Au or Ag.