In metallurgy,flux is used to:

Extraction of a metal $(M)$ from its sulfide ore $(M_2S)$ involves the following chemical reactions:
$2M_2S + 3O_2 \xrightarrow{\text{heat}} 2M_2O + 2SO_2 \uparrow$
$M_2S + 2M_2O \xrightarrow{\text{heat}} 6M + SO_2 \uparrow$
The metal $(M)$ may be

Explain the reduction process involved in the extraction of zinc.

The purest form of iron is:

Blister copper is.......

What is the process of metallurgy?