In the extraction of \(Al\) metal from Bauxite ore, the correct sequence of various processes involved is:

1. Heating the ore to remove volatile impurities
2. Electrolysis of molten ore-mixture
3. Leaching of aluminium with concentrated \(NaOH\)
4. Grading and crushing of big ore particles
5. Mixing alumina with \(CaF_2\) or \(Na_3AlF_6\)

Choose the correct answer from the options given below:

D, B, C, A, E

The correct answer is (1) D, B, C, A, E.

The correct sequence of processes involved in the extraction of \(Al\) metal from Bauxite ore is:

D. Grinding and crushing of big ore particles

This step is necessary to increase the surface area of the ore particles, which facilitates the subsequent leaching process.

B. Electrolysis of molten ore-mixture

The ore is not directly electrolyzed. Instead, alumina, the purified form of aluminum oxide, is electrolyzed in a molten mixture of cryolite \((Na_3AlF_6)\) and alumina.

C. Leaching of aluminium with concentrated \(NaOH\)

This step is known as the Bayer process and involves leaching the crushed bauxite ore with a concentrated solution of sodium hydroxide \((NaOH)\). This process dissolves the aluminum hydroxide \((Al(OH)_3)\) present in the bauxite ore, leaving behind the impurities as a red mud residue.

A. Heating the ore to remove volatile impurities

This step is sometimes included in the bauxite processing prior to the Bayer process to remove some of the volatile impurities present in the ore, such as water and carbon dioxide.

E. Mixing alumina with \(CaF_2\) or \(Na_3AlF_6\)

This step is necessary to lower the melting point of alumina, which is too high to be electrolyzed directly. Cryolite \((Na_3AlF_6)\) is the most commonly used flux for this purpose.

Therefore, the correct sequence of processes involved in the extraction of \(Al\) metal from Bauxite ore is 1. D, B, C, A, E.