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why are metals sulphide and carbonate converted into metal oxide prior to reduction during the extraction of metals . explain by giving one example in each case

Conversion of concentrated ore into metal oxide 
It is easier to obtain metals from their oxides rather than from carbonates or sulphides. So the ore is first converted into an oxide. A carbonate ore is first converted into oxide ore by calcination. A sulphide ore is converted into oxide ore by roasting. 

1. Calcination process 
It is the process of heating the concentrated ore at a temperature not sufficient to melt the ore. The water content and the volatile impurities also get expelled. Zinc carbonate in its ore calamine (ZnCO3) is calcinated to obtain zinc oxide (ZnO). 
 
 

ZnCO3------------->ZnO+CO2
 calcination   

2. Roasting process 
It is the process of heating the concentrated ore in the presence of excess air. Volatile impurities also get expelled. 
Zinc sulphide in its ore zinc blende ( ZnS) is roasted to obtain zinc oxide (ZnO). 
 
 

2ZnS+3O2----->2ZnO+2SO2
  (from air)    

Mercuric oxide is obtained by roasting cinnabar (HgS) in air. 
 
 

2ZnS+3O2----->2ZnO+2SO2

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Beacuse metals such as iron, zinc, lead, copper etc.. are usually present as sulphides or carbonates in nature. It is easier to obtain a metal from its oxide, as compared to sulphides and carbonates. Therefore, prior to reduction, the metal sulphides and carbonates must be converted into metal oxides..

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It is easier to reduce a metal from its oxide as compared to its sulphides and carbonates. Hence, usually the metal sulphides and carbonates are converted to metal oxides before the reduction during the extraction process.

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​Reducing metals by removing oxygen is easier than directly removing carbonatesor sulphides .Carbonates are changed to oxides through a process called calcination.In this process the mineral is heated in absence of air
E.g.CaCO3-CaO+CO2 .
Sulphides are changed to oxides by a process called roasting. In this process the mineral is heated in presence of air
E.g. CuFeS2 + O2 - CU2S + 2Fe + SO2
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good answer

































 
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It is easier to obtain metals from their oxides rather than from carbonates or sulphides. So the ore is first converted into an oxide. A carbonate ore is first converted into oxide ore by calcination. A sulphide ore is converted into oxide ore by roasting.

1. Calcination process
It is the process of heating the concentrated ore at a temperature not sufficient to melt the ore. The water content and the volatile impurities also get expelled. Zinc carbonate in its ore calamine (ZnCO3) is calcinated to obtain zinc oxide (ZnO).

2. Roasting process
It is the process of heating the concentrated ore in the presence of excess air. Volatile impurities also get expelled.
Zinc sulphide in its ore zinc blende ( ZnS) is roasted to obtain zinc oxide (ZnO).
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?Reducing metals by removing oxygen is easier than directly removing carbonatesor sulphides .Carbonates are changed to oxides through a process called calcination.In this process the mineral is heated in absence of air
E.g.CaCO3-CaO+CO2 .
Sulphides are changed to oxides by a process called roasting. In this process the mineral is heated in presence of air
E.g. CuFeS2 + O2 - CU2S + 2Fe + SO2
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Respective metals can be easily obtained from their oxides rather than their sulphide or carbonate ores because oxygen has less affinity with metals as compared to sulphides and carbonate ores.... Therefore metals are first converted to their respective oxides... Hope yu like it...CHEERS..🍻🍻
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Please answer why is it easy
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