What is inorganic benzene? How is it formed?

Copper is extracted from copper pyrites, CuFeS_2 .What is matte? How is it formed?

Assertion : Borazole, known as inorganic benzene is more reactive than benzene Reason : In borazole, B-N bonds are polar whereas in benzene C-C are non polar (I) Both assertion and reason are correct and reason is the correct explanation of assertion. (II) Both assertion and reason are correct and reason is not the correct explanation of assertion. (III) Assertion is true and reason is false (IV) Assertion is false,reason is true

How the ions are formed?

What are free radicals? How are they formed?