Question

Which of the following metals can be extracted through alkali leaching technique?

• A. Cu
• B. Au
• C. Sn
• D. Pb

Answer 1

The Correct Option is C

The process of alkali leaching is used to extract certain metals from their ores by converting them into soluble compounds that can easily be separated from the gangue. This technique exploits the chemical properties of the metal components; specifically, it often uses the solubility of metal-containing compounds in alkaline solutions to facilitate extraction.

Among the options given:

• Cu (Copper): Copper is typically extracted from its sulfide ores using methods like roasting and smelting, not through alkali leaching.
• Au (Gold): Gold is commonly extracted using the cyanidation process rather than alkali leaching.
• Sn (Tin): Tin is extracted using alkali leaching. The ore Cassiterite (\text{SnO}_2) is subjected to alkaline leaching, usually with sodium hydroxide (NaOH), to separate out insoluble impurities, making tin a suitable candidate for this technique.
• Pb (Lead): Lead is generally extracted using high-temperature processes like roasting and smelting, not by alkali leaching.

Therefore, the correct answer is Sn (Tin), as it can be extracted through alkali leaching technique effectively.