Question

Sulphide ores of metals are usually concentrated by froth floatation process. Which one of the following sulphide ores offers an exception and is concentrated by chemical leaching?

• A. Argentite
• B. Galena
• C. Copper pyrite
• D. Sphalerite

Answer 1

The Correct Option is A

In the given question, we need to identify which sulphide ore among the options is concentrated by chemical leaching instead of the froth flotation process.

Froth flotation is a widely used method for concentrating sulphide ores. However, certain sulphide ores are not suited for this method and are instead concentrated using chemical leaching. This is particularly the case with ores that either have high purity forms or are not easily separated through froth flotation.

Among the options provided:

• Argentite (Ag₂S): Argentite is typically concentrated using chemical methods such as cyanidation (leaching with cyanide) due to its silver content. This is because silver can be effectively extracted by dissolving it in cyanide solution, which makes cyanidation more suitable.
• Galena (PbS): Galena is generally concentrated using the froth flotation process due to its lead content, which responds well to this method.
• Copper Pyrite (CuFeS₂): This copper sulphide ore is also commonly concentrated by froth flotation, a method well-suited to its properties.
• Sphalerite (ZnS): Like galena, sphalerite is also commonly concentrated by froth flotation due to the nature of zinc concentration.

Conclusion: Out of the options provided, Argentite is the exception as it is concentrated by chemical leaching, specifically cyanidation. Therefore, the correct answer is Argentite.