Question

Sulfide ores are concentrated by

• A. froth floatation
• B. smelting
• C. roasting
• D. reduction

Hint:

Froth flotation is a process used for the concentration of sulfide ores, where the ore is separated from the gangue by exploiting differences in their ability to adhere to air bubbles.

Answer 1

The Correct Option is A

Step 1: Understanding sulfide ore concentration.
Sulfide ores, such as zinc sulfide (ZnS) or copper pyrite (CuFeS\(_2\)), are primarily concentrated by froth flotation. This method involves creating a froth in which hydrophobic particles (usually the ore particles) are attached to air bubbles and rise to the surface, where they can be removed.
Step 2: Explanation of options.
- Option (A) Froth floatation: This is the correct method for concentrating sulfide ores by exploiting the differences in the hydrophobicity of the ore particles and gangue.
- Option (B) Smelting: Smelting involves the reduction of metal oxides to metals, but it is not used for concentrating sulfide ores.
- Option (C) Roasting: Roasting is the process of heating sulfide ores in the presence of oxygen, causing oxidation and removal of sulfur, but it is not a concentration method, it is a purification method.
- Option (D) Reduction: Reduction is used to obtain metals from their oxides, not for concentrating sulfide ores.
Step 3: Conclusion.
Froth flotation is the method used to concentrate sulfide ores by separating the ore particles from the gangue based on differences in their hydrophobicity.
Final Answer: \[ \boxed{\text{Froth flotation is used to concentrate sulfide ores.}} \]