Discuss some of the factors, which need consideration before deciding on the method of extraction of metal from its ore.

Explanation

The extraction of metals involves the following chemical processes:
i) Conversion of ore into metal oxide
iii) Reduction of oxide. to the -free metal. The method used for the above processes depends on the nature of the dre. Eg, metals are usually. poresent in ores aš hydtoxides, carbonates ind suphides. Calcination is used for converting metă! carbonates and hydroxides into their respective ox ides. While roasting is used for the conversion,of sulphide ores to their oxides. The roasted or calcined ore is then reduced to the metal.using suitable reducing agent. If the metal to .be extracted is very reactive metal like atkali metals, alkaline earth metals and aluminium, reduction is carried out by electrolytic method. The oxides of less reactive metals like zinc, iron, copper, lead, tifi:
iranganese, chromium etc, can be reduced by sutt able reducing agents, which is selected based on thermodynamic principles, using Ellingham diagram.