Question 5 - Assertion Reasoning Questions (MCQ) - Chapter 3 Class 10 - Metals and Non-Metals

Assertion (A): In the metallurgy of Al, purified  Al ₂ O ₃ is mixed with Na ₃ AlF ₆ or CaF ₂ .  

Reason (R): It lowers the melting point of the mixture and brings conductivity.  

Ans. 

In the metallurgy of aluminium using the Hall-heroult process, 

• Purified Al ₂ O ₃ is mixed with Na ₃ AlF ₆ or CaF ₂  
• It lowers the melting point of the mixture and increases electrical conductivity .  
• This makes it easier for the electrolyte to conduct electricity and hence refine Al using Carbon Reduction. 

Thus, 

• The Assertion is True.
• Reason is also True.

And the Reason is the correct explanation for the assertion.  

So, the correct answer is (a)