Question

The chemical is added to reduce the melting point of the reaction mixture during the extraction of aluminum is

• A. Cryolite
• B. Calamine
• C. Kaolite
• D. Bauxite

Answer 1

The correct option is A

Cryolite

The explanation for the correct option:

Option (A): Cryolite

1. Electrolysis is the process of converting electrolytes into elements by utilizing electricity. For a specific electrolyte, the electrolysis's byproducts can be predicted. This process is used to extract some metals from their ore, including aluminium.
2. Although aluminium is the most common metal on Earth, it is expensive in large part due to the quantity of electricity required for its extraction.
3. Bauxite is the name for aluminium ore (${\mathrm{Al}}_2{\mathrm{O}}_3$). Bauxite is refined to create aluminium oxide, commonly known as alumina, which can be used to extract aluminium.
4. the aluminium oxide must first be melted in order for electricity to pass through it. However, melting aluminium oxide would be expensive due to its extremely high melting point (about ${2000}^{°}\mathrm{C}$).
5. It is instead dissolved in molten cryolite(${\mathrm{Na}}_3{\mathrm{AlF}}_6$), a type of aluminium compound with a lower melting point than aluminium oxide.
6. Because the ions in aluminium oxide can flow more easily at a lower temperature when using molten cryolite as a solvent, some of the energy expenses associated with extracting aluminium are reduced.
7. Hence, it is the correct option.

The explanation for the incorrect options:

Option (B): Calamine

1. It is an ore from which Zinc is formed
2. In place of the former impure carbonate known as calamine, zinc carbonate is mostly utilised in ointments.
3. Hence, it is an incorrect option

Option (C): Kaolinite

1. It is a clay mineral with a formula ${\mathrm{Al}}_2{\mathrm{Si}}_2{\mathrm{O}}_5{\left(\mathrm{OH}\right)}_4$
2. Brick, pottery, and tile can all be made from kaolinite.
3. Hence, it is an incorrect option

Option (D): Bauxite

1. Bauxite ore is a soft, red clay that is abundant in alumina.
2. It is the only mineral utilized in the large-scale manufacture of aluminium and it also serves as a mineral for the industry.
3. Hence, it is an incorrect option

Therefore, Cryolite is added to reduce the melting point of the reaction mixture during the extraction of aluminium.