Question

Electromagnetic separation is used in the concentration of:
A. Copper pyrite
B. Bauxite
C. Cassiterite
D. Cinnabar

Answer 1

Electromagnetic separation is a technique used to extract metals from their ores. An ore is a substance that has a metal along with other elements or minerals. This technique involves the separation of the material that can be attracted to a magnetic field from the material that cannot be attracted to a magnetic field.

Complete answer:
Electromagnetic separation is the method to concentrate the ore or to remove unwanted materials like sand and clay from the ore. Magnetic or electromagnetic separation is the technique based on differences in magnetic properties of the ore or gangue. The particles that are attracted with the magnetic field are separated out.
The ores of metals that contain either the metal or the impurity to be magnetic can be separated by electromagnetic separation. Since the ore of copper that is copper pyrite that is $CuFe{{S}_{2}}$ contains iron that has magnetic properties, therefore this ore can be used in this technique for concentration.
Hence, electromagnetic separation is used in the concentration of copper pyrite.

So option A is correct.

Note:
Bauxite is an ore of aluminum having formula $A{{l}_{2}}{{H}_{2}}{{O}_{4}}$ this is concentrated by leaching process, while cassiterite is an ore of tin that is tin oxide $Sn{{O}_{2}}$, so it is extracted by simply calcination process. Cinnabar is an ore of mercury sulphide having formula HgS, it is concentrated by flotation method or gravity involving methods.