Undesired earthy impurities or substances associated with ore are called gangue. For example: Soil, sand, stones and silicates.
b. What is leaching? Give one example.
The removal of soluble materials from a substance which as soil sand Rock etc through the percolation of water is called leaching.
i.e, separation are called from river sand by water washing process.
c. All ores minerals for all minerals are not ores. explain.
All minerals cannot be ores because the contain unwanted substance other than metals where as all ore can be minerals as we can extract metal commercially.
d. Why all ores are minerals but all minerals are not ores?
- Ores are the minerals having high concentration of elements mostly metals. Example-Ore of Mercury, ore of Tin, ore of Zinc.
- Minerals are the naturally occurring chemical substances having fixed chemical composition and crystalline structure. Example- Table salt (Sodium chloride), quartz (Silicon dioxide),limestone.
- All minerals cannot be ores because they contain unwanted substances other than metals whereas all ores can be minerals as we can extract metal commercially.
e. What is ore?
That matters can be extracted from the minerals profitably such minerals is called ore.
f. What is minerals?
The metal or substance in free or combine state is called minerals.
g. What is alloy?
Homogeneous mixture of metal with other elements is called alloy.
h. Define amalgam.
If one of the component of the alloy is mercury the alloy is called amalgam.
i. Define metallurgy. Explain the types of metallurgy.
In arts and science of extracting metal from their ores and the technology for their use is called metallurgy.
Based on the method of reduction used metrology can be broadly classified into three types:-
1. Pyrometallurgy : pyrometallurgy is an arts and science to extract and purify the metals by the forces involving the applications of heat.
2. Hydrometallurgy : it is a method of extracting metal from the aqueous solution of metallic or using precipitation method, in this type of metallurgy the method of reduction is precipitation.
3. Electro-metallurgy : In this method to extract and purify the metals by using electric energy. In this case, the method of reduction is electrolysis.
Flux: The substance which is added into processing or to convert the infusible impurity into light fusible mass is called flux.
Slag: The fusible mass is called slag.
Gangue + Flux ————» Slag
Calcination: A process of heating and concentrated ore at a temperature blow its melting point in absence of year to convert the ore into dry metallic oxide form is called calcination calculation is done for oxide or hydroxide or carbonate ores as they do not required oxygen to be converted into the metallic oxide.
Roasting: A process of heating the concentrated ore at a temperature below its melting point in presence of excess of air to convert the ore into dry metallic oxide form is called roasting.
Roasting is done for non oxide forms of metal this process is also carried out in reverberatory furnaces or sinterers.
Alumino thermic process:
Zone refining:
Poling: This method is used when the metallic oxide are present as impurities after the extraction in the metallurgy of Cu and Pb. In this method, the molten metal mass is stirred with green wood poles. The hydrocarbon present in the greenhouse reduce the metallic oxide into three metal. for example :
CU2O + hydrocarbon ———› Cu + CO2 + H2O
Forth flotation: In this method, powdered is mixed with water and wild and ethyl xanthate in a big tank the mixture is agitated by blasting of air and the gangue of particle are settled down and the forth of metal is sinking over.
