MCQ Detailed View

Parke’s process is an important method used in metallurgy for the extraction of silver from its ores, particularly from lead ores like argentiferous galena (PbS containing silver). In this process, molten lead containing silver is treated with zinc, which selectively dissolves silver due to its higher affinity for silver.

The steps of Parke’s process are as follows:

1. 
   

   Lead containing silver is melted in a suitable furnace.

   
   


2. 
   

   Zinc is added to the molten lead. Silver dissolves preferentially in zinc forming a separate alloy layer.

   
   


3. 
   

   The zinc-silver alloy is then separated from the molten lead.

   
   


4. 
   

   Finally, silver is extracted from the zinc by distillation, as zinc has a lower boiling point and evaporates, leaving behind pure silver.

   
   

Parke’s process is significant because it allows for efficient recovery of silver from lead, which would otherwise remain in the lead metal. This process demonstrates key principles of selective affinity, liquid-liquid extraction, and distillation in metallurgy.

Other metals are not extracted by Parke’s process:

• 
  

  Iron is extracted using the blast furnace.

  
  


• 
  

  Sodium is obtained by electrolysis of molten salts (Downs process).

  
  


• 
  

  Zinc is extracted by roasting and reduction using carbon or electrolysis.

  
  

Understanding Parke’s process is essential in inorganic chemistry, as it illustrates practical applications of metal extraction, refining techniques, and the use of chemical properties to separate metals. It also highlights the importance of alloy formation and distillation in obtaining high-purity metals.