differentiate between calcination and roasting taking examples of zinc ores
Answers
Answer:
Calcination means heating of ore below its m. p in absence of air and roasting is in presence of air
Answer:
Roasting is the process of obtaining sulphur from sulphur ore in the presence of air or oxygen.
During roasting, the sulfide is converted to an oxide, and sulfur is released as sulfur dioxide, a gas. For the ores Cu2S (chalcocite) and ZnS (sphalerite), balanced equations for the roasting are:
2 Cu2S + 3 O2 → 2 Cu2O + 2 SO22 ZnS + 3 O2 → 2 ZnO + 2 SO2
The gaseous product of sulfide roasting, sulfur dioxide (SO2) is often used to produce sulfuric acid(H2SO4).
Calcination is the process of getting carbon from its ore in the absence of air.
For example, in limestone calcination, a decomposition process, the chemical reaction is
CaCO3 → CaO + CO2(g)
we can extract zinc by carbon reduction
Extraction of Zinc - Zinc is extracted through carbon reduction of the ore Zinc blende (ZnS) ore by specially designed blast furniture