To obtain steel entirely free from sulphur and phosphorus,the process used is

The process of the extraction of copper from copper pyrites involves:-
$(I)$ Froth floatation $(II)$ Calcination $(III)$ Roasting $(IV)$ Self reduction $(V)$ Smelting $(VI)$ Liquation $(VII)$ Electrorefining

Steel is manufactured from

Which of the following is not a basic flux?

The advantage$(s)$ of using $O_2$ rather than air in the steel industry is(are):
$(I)$ There is a faster conversion,so a given plant can produce more steel in a day.
$(II)$ Larger quantities can be handled.
$(III)$ It gives a purer product,and the surface is free from nitrides.

Which of the following statements is not correct?