Home
Class 12
CHEMISTRY
Electrolytic reduction of alumina to alu...

Electrolytic reduction of alumina to aluminium by Hall-Heroult process is carried out:

A

in the presence of `NaCl`

B

in presence of fluorite

C

in presence of cryolite which forms a melt with lower melting temperature

D

in the presence of cryolite which forms a melt with higher melting temperature

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question regarding the electrolytic reduction of alumina to aluminum by the Hall-Heroult process, we can follow these steps: ### Step 1: Understanding the Hall-Heroult Process The Hall-Heroult process is an industrial method for extracting aluminum from its oxide, alumina (Al₂O₃). The process involves the electrolysis of a molten mixture of alumina and a solvent. **Hint:** Research the Hall-Heroult process to understand its significance in aluminum extraction. ### Step 2: Identifying the Components Used In the Hall-Heroult process, alumina is dissolved in a molten solvent, which is typically cryolite (Na₃AlF₆). Cryolite serves as a solvent to lower the melting point of alumina and improve the electrical conductivity of the mixture. **Hint:** Look up the chemical formula of cryolite and its role in the electrolysis process. ### Step 3: Role of Cryolite Cryolite not only reduces the melting point of alumina but also enhances the conductivity of the electrolyte. This is crucial for efficient electrolysis, as higher conductivity allows for better current flow. **Hint:** Consider why lowering the melting point is beneficial in industrial processes. ### Step 4: Additional Components Sometimes, small amounts of other compounds like AlF₃ and CaF₂ are added to further enhance conductivity and efficiency during the electrolysis. **Hint:** Investigate the effects of other additives on the electrolysis process. ### Step 5: Conclusion The electrolytic reduction of alumina to aluminum in the Hall-Heroult process is carried out in the presence of cryolite, which forms a melt with a lower melting point, facilitating the process. **Hint:** Summarize the overall process and the importance of each component involved. ### Final Answer The electrolytic reduction of alumina to aluminum by the Hall-Heroult process is carried out in the presence of cryolite. ### Answer Option Option number 3: In the presence of cryolite.
Promotional Banner

Similar Questions

Explore conceptually related problems

Electrolytic reduction of alumina to aluminum by the Hall-Heroult process is carried out

In the electrolytic reduction of pure alumina to pure aluminium - by Hall Herault's process, give the electrolytic reaction involved in the same, resulting in formation of aluminium at the cathode.

Hall-Heroult's process is given by :

The funciton of adding cryolite in the electrolytic reduction of alumina by Hall-Heroult process is to :

Name the following : The non-metal which forms the anode during electrolytic reduction of fused alumina in Hall Heroult's process.

The reduction of an oxide by aluminium is called

Answer the following questions based on the ectraction of aluminium from alumina by Hall - Heroult's Process. Why is powdered coke sprinked on top of the electrolyte.

Answer the question based on the extraction of aluminium from alumina by Hall Heroult's Process : What is sprinkled on top of the electrolyte ?

Answer the following questions based on the ectraction of aluminium from alumina by Hall - Heroult's Process. What is the function of cryolite used along with alumina as the electrolyte.

(ii) Iron can reduce alumina to aluminium metal.