What is the process of converting a sulphide ore into its oxide by heating it strongly in excess air called?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Roasting
Roasting is the strong heating of a sulphide ore in excess air, which turns it into the metal oxide and gives off sulphur dioxide; for example, zinc sulphide changes to zinc oxide.
Why the other options are incorrect
Option (1) Calcination — Incorrect. Strong heating of a carbonate ore in limited air, which gives the oxide and carbon dioxide.
Option (3) Smelting — Incorrect. Heating the ore with a reducing agent such as coke so that the metal is obtained in molten form.
Option (4) None of these — Incorrect. Roasting is the name of this process.