Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
Olympiad workbookNSECGeneral Principles and Processes of Isolation of Metals

During extraction of gold, the gold ore is treated with aqueous KCN solution as shown by the equations (not balanced) below to get compound X which is further reduced by Zn to obtain compound Y and metallic gold. Identify X and Y . aligned & Gold ore + CN ⁻+ H ₂ O + O ₂ [ X ]+ OH ⁻ (i) & [ X ]+ Zn [ Y ]+ Au (ii) aligned

Options

  1. AX = [ Au ( CN )₂ ]⁻, Y = [ Zn ( CN )₂ ]²⁻
  2. BX = [ Au ( CN )₂ ]⁻, Y = [ Zn ( CN )₄ ]²⁻
  3. CX = [ Au ( CN )₄ ]³⁻, Y = [ Zn ( CN )₄ ]²⁻
  4. DX = [ Au ( CN )₂ ], Y = [ Zn ( CN )₄ ]⁴⁻

Correct answer

B. X = [ Au ( CN )₂ ]⁻, Y = [ Zn ( CN )₄ ]²⁻

Step-by-step solution

No Solution

Practice General Principles and Processes of Isolation of Metals on Quantrex Academy →

More from General Principles and Processes of Isolation of Metals

P, Q, R and S are four metals whose typical reactions are given below. (I) Only Q and R react with dilute HCl to give H ₂ gas. (II) When Q is added to a solution containing the ionThe following Ellingham diagram depicts the oxidation of ' C ', ' CO ' and ' Fe '. Which of the following is correct? I. FeO can be reduced by C below 600 K II. FeO can be reduced Ellingham diagrams are plots of G ^0 vs temperature which have applications in metallurgy. 2 H ₂+ O ₂=2 H ₂ O G ( ~J )=-247500+55.85 ~T (I)2 CO + O ₂=2 CO ₂ G ( ~J )=-282400+86.81 Aluminium and copper are extracted from their oxide and sulphide ores respectively Which of the following is correct? I. Copper is extracted by the auto reduction of copper oxide bConsider the following statements: (i) Calcination is carried out in absence of air below the melting point of the ore (ii) Roasting and calcination are carried out in presence of Full General Principles and Processes of Isolation of Metals list All Olympiad workbook PYQs