Advertisements
Advertisements
प्रश्न
What is the role of zinc metal in the extraction of silver ?
Advertisements
उत्तर
Silver is extracted from the ore-argentite (Ag2S). This process of extraction of silver is called as cyanide process as sodium cyanide solution is used. The ore is crushed, concentrated and then treated with sodium cyanide solution. This reaction results into sodium argento cyanide Na[Ag(CN)2]. The reaction is as follows:
AgS + 4NaCN ⇌ 2Na[Ag(CN)2] + Na2S
The solution of sodium argento cyanide combines with zinc dust. It forms sodium tetra cyanozicate and precipitates silver. This precipitated silver is called as spongy silver. The reaction is as follows:
Zn + 2Na[Ag(CN)2] → Na2[Zn(CN)4] + 2Ag
The spongy silver is fused with potassium nitrate to get pure silver. This silver obtained is purified by electrolytic process.
APPEARS IN
संबंधित प्रश्न
What is calcination?
Explain calcination with reactions.
Define Hydrometallurgy?
Which solution is used for the leaching of silver metal in the presence of air in the metallurgy of silver?
MnO2 and Ca3(PO4)2 present in iron ore get reduced to Mn and P in the zone of _______.
(A) combustion
(B) reduction
(C) fusion
(D) slag formation
An element X (molar mass = 60 g mol−1) has a density of 6.23 g cm−3. Identify the type of cubic unit cell, if the edge length of the unit cell is 4 ✕ 10−8 cm.
Which metal is also found in sea beds?
Which of the following reactions is an example of autoreduction?
Brine is electrolysed by using inert electrodes. The reaction at anode is ______.
Why are sulphide ores converted to oxide before reduction?
