Question

 

When copper pyrites is roasted in excess of air, a mixture of CuO + FeO is formed. FeO is present as impurities. This can be removed as slag during reduction of CuO. The flux added to form slag is

Solution

Correct option is

SiO2 which is an acid flux

 

The compounds which combine with impurities present in ore (at high temperature) and remove them as a fusible substance (slag) are known as flux. When basic impurities are present, an acidic flux is used and vice-versa.  

           

   Basic impurity             acidic flux                  slag

SIMILAR QUESTIONS

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Pb and Sn are extracted from their chief ore by

Q2

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Q3

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Q4

Which of the following is correct?

Q5

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Q6

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Q7

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Q8

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Q9

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Q10

Willemite is