The process of heating an ore in the presence of excess air to a temperature below its melting point is called:

Consider the following statements:
Roasting is carried out to:
$(i)$ convert sulphide to oxide and sulphate
$(ii)$ remove water of hydration
$(iii)$ melt the ore
$(iv)$ remove arsenic and sulphur impurities
Of these statements:

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:

Why are sulphide ores converted to oxide before reduction?

Why is iron pyrite not the ideal choice of ore for the extraction of iron?

When limestone is heated,$CO_{2}$ is given off. The metallurgical operation is