In the cyanide extraction process of silver from argentite ore, the reducing agent used is:
In the cyanide extraction process of silver from argentite ore, the reducing agent used is dust.
The cyanide extraction process, also known as the cyanidation process, is commonly used to extract silver and gold from their ores. In this process, the ore is first finely ground and then mixed with a dilute solution of sodium cyanide and water. The sodium cyanide forms a complex with silver ions
, known as a silver cyanide complex.
The silver cyanide complex is then reduced to metallic silver by a suitable reducing agent. In the case of silver extraction, dust (finely powdered zinc) is commonly used as the reducing agent. The reaction can be represented as follows:
Here, dust reacts with the silver cyanide complex, reducing it to elemental silver and forming zinc cyanide
as a byproduct.
Therefore, in the cyanide extraction process of silver from argentite ore, dust is used as the reducing agent. Hence, option 4) "Zn dust" is the correct choice.