Explain the extraction process of metals from their ores based on their position in the activity series. Specifically de

Question

Explain the extraction process of metals from their ores based on their position in the activity series. Specifically detail: Extraction of metals low in the reactivity series (with suitable chemical equations). Differentiate between Roasting and Calcination with chemical equations for metals in the middle of the reactivity series.

Accepted Answer

Extraction of Metals Based on Reactivity 
Metals are extracted from their ores based on their reactivity order in the activity series: --- Extraction of Metals Low in the Reactivity Series
Metals low in the reactivity series are very unreactive. The oxides of these metals can be reduced to metals by heating alone. Example: Extraction of Mercury from Cinnabar ($HgS$): Step 1: Cinnabar ($HgS$) is first heated in air to convert it into mercuric oxide ($HgO$). $$2HgS(s) + 3O2(g) \xrightarrow{\Delta} 2HgO(s) + 2SO2(g)$$ Step 2: Mercuric oxide is then reduced to mercury metal upon further heating. $$2HgO(s) \xrightarrow{\Delta} 2Hg(l) + O2(g)$$ Example: Extraction of Copper from Copper Pyrites/Glance ($Cu2S$): $$2Cu2S(s) + 3O2(g) \xrightarrow{\Delta} 2Cu2O(s) + 2SO2(g)$$ $$2Cu2O(s) + Cu2S(s) \xrightarrow{\Delta} 6Cu(s) + SO2(g)$$ --- Difference Between Roasting and Calcination 
Metals in the middle of the reactivity series (like $Fe, Zn, Pb$) are usually present as sulphides or carbonates in nature. Before reduction, they are converted into metal oxides using Roasting or Calcination. | Feature | Roasting (भर्जन) | Calcination (निस्तापन) | | :--- | :--- | :--- | | Definition | The process of heating sulfide ores strongly in the presence of excess air. | The process of heating carbonate ores strongly in limited air or absence of air. | | Type of Ore | Used for Sulphide ores. | Used for Carbonate ores. | | Gas Evolved | Sulphur dioxide ($SO2$) gas is liberated. | Carbon dioxide ($CO2$) gas is liberated. | | Chemical Reaction Example | Zinc Sulphide ($ZnS$):$2ZnS(s) + 3O2(g) \xrightarrow{\Delta} 2ZnO(s) + 2SO2(g)$ | Zinc Carbonate ($ZnCO3$):$ZnCO3(s) \xrightarrow{\Delta} ZnO(s) + CO2(g)$ | 
After obtaining the metal oxide ($ZnO$), it is reduced to metallic zinc using a suitable reducing agent such as carbon (coke): $$ZnO(s) + C(s) ightarrow Zn(s) + CO(g)$$

Metals and Non-metals

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