In the cyanide process for extraction of gold | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) Silver and gold are extracted by the cyanide process (Mac Arthur - Forrest process). After the preliminary crushing and concentration by froth flo

Vedclass · Accepted Answer

leaching agent to bring gold and silver into solution as cyanide complexes and thus separate these metal from impurities

Vedclass · Answer

(B) Silver and gold are extracted by the cyanide process (Mac Arthur - Forrest process). After the preliminary crushing and concentration by froth floatation process,the ore (crushed auriferous rocks in the case of gold) is leached with a dilute $(0.4 - 7\, \%)$ solution of sodium cyanide made alkaline by adding lime and kept agitated by a current of air. Silver (or gold) passes into the solution as argentocyanide (or aurocyanide). It is based on the fact that gold/silver dissolves in a dilute solution of sodium cyanide in the presence of atmospheric oxygen with the formation of a complex cyanide. Reaction: $4Au + 8NaCN + 2H_2O + O_2 \rightarrow 4Na[Au(CN)_2] + 4NaOH$ $Ag_2S + 4NaCN \rightarrow 2Na[Ag(CN)_2] + Na_2S$ Silver is obtained by reaction with $Zn$: $2Na[Ag(CN)_2] + Zn \rightarrow Na_2[Zn(CN)_4] + 2Ag$

In the cyanide process for extraction of gold and silver from ores,the cyanide solution acts as a

Similar Questions

Which of the following ores cannot be concentrated by the froth flotation method?

In the process of extracting alumina from bauxite,bauxite is concentrated by $......$.

Chemical leaching is useful in the concentration of

In the froth floatation process for the concentration of ores,the ore particles float because:

The process which involves the treatment of the ore with a suitable reagent so as to make it soluble but not the impurities is called:

Vedclass Test Series

Exam Paper Generator

Online Exam Module