What is the name of the process that converts sulphide ores into oxides by heating strongly in the presence of excess air ?
Calcination
Roasting
Smelting
Incineration
Answer is Wrong!
Answer is Right!
This question was previously asked in
UPSC CDS-2 – 2021
2MS(s) + 3O₂(g) → 2MO(s) + 2SO₂(g) (where M is the metal)
For example, roasting of zinc sulphide: 2ZnS(s) + 3O₂(g) → 2ZnO(s) + 2SO₂(g).
Calcination involves heating a carbonate or hydroxide ore strongly in limited or no air to decompose it into an oxide.
Smelting is a process of using heat to extract a metal from its ore, often involving a reducing agent, and doesn’t specifically focus on converting sulphide to oxide in air.
Incineration is the burning of waste.
Therefore, roasting is the correct term for converting sulphide ores to oxides by heating in excess air.
– It requires heating in the presence of excess air.
– It converts the sulphide into a metal oxide and releases sulphur dioxide.