The chemical reaction that involves roasting process is
Fe2O3 + 3CO → 2Fe + 3CO2
2Al + Fe2O3 → 2Fe + Al2O3
2ZnS + 3O2 → 2ZnO + 3SO2
FeO + SiO2 → FeSiO3
Which one of the following oxides is reduced by water gas to obtain the metal during its extraction?
NiO
ZnO
WO3
Fe2O3
Which of the following is not added durig the extraction of silver by cyanide process?
NaCN
Air
Zn
Na2S2O3
What is the role of limestone during the extraction of iron from haematite ore?
Leaching agent
Oxidising agent
Reducing agent
Flux
Which of the following process involve heating?
Calcination
Smelting
Roasting
Levgation
D.
Levgation
Levigation is the process of seperating the lighter gangue particles from the heavier ore particles by washing in current of water. This is also called gravity seperation or hydraulic washing and is generally used for oxides ores and carbonates ores and carbonate ores. In other processes, calcination, smelting and roasting, there is heating.
After partial roasting the sulphide of copper is reduced by
reduction by carbon
electrolysis
self-reduction
cyanide process