Question

converts sulphides to oxides. converts carbonates to oxides.

• A. Calcination
• B. Heating
• C. Roasting
• D. Refining

Answer 1

Answer: (A), (C)

Roasting

Sulphide ores are converted into oxides by heating strongly in the presence of excess air. This process is known as roasting.
For example:
$2\mathrm{ZnS}\left(s\right)+3O_2\left(g\right)\to 2\mathrm{ZnO}\left(s\right)+2{\mathrm{SO}}_2\left(g\right)$
Carbonate ores are converted into oxides by heating strongly in the absence of air. This process is known as calcination. For example:${\mathrm{CaCO}}_3\left(s\right)\to \mathrm{CaO}\left(s\right)+{\mathrm{CO}}_2\left(g\right)$