The process of roasting of an ore is carried out in the

Roasting is done in

The process of heating the ore strongly in excess of air so that the volatile impurities are removed and the ore is changed to oxide is known as

Roasting of copper pyrites ores is for the following purposes:

Consider two chemical reactions $(A)$ and $(B)$ that take place during metallurgical processes:
$(A)$ $ZnCO_{3(s)} \longrightarrow ZnO_{(s)} + CO_{2(g)}$
$(B)$ $2ZnS_{(s)} + 3O_{2(g)} \longrightarrow 2ZnO_{(s)} + 2SO_{2(g)}$
The correct names for these processes are:

In what form should the concentrated ore be converted? Why?