Question

Write a note on the extraction of less reactive metals.

Answer 1

Less reactive metals such as copper, mercury, silver and gold are generally extracted from their ores by relatively simple methods.

1. Concentration of ore: The ore is first concentrated by suitable methods such as hydraulic washing or froth flotation.
2. Heating of ore: Some less reactive metals can be obtained by heating their ores. For example, mercury is obtained by roasting cinnabar:
   \[\ce{HgS + O2 -> Hg + SO2}\]
3. Reduction: The oxides of less reactive metals can often be reduced by heating or using a suitable reducing agent.
4. Refining: The metal obtained is purified by suitable methods such as electrolytic refining.

Thus, less reactive metals require comparatively less energy for extraction than highly reactive metals.