Exams › JEE Advanced › Chemistry
Which of the following processes are involved in the commercial extraction of gold?
- Amalgamation only
- Cyanide (Mac-Arthur Forrest) process only
- Both amalgamation and cyanide process
- Neither of the above
Correct answer: Both amalgamation and cyanide process
Solution
Gold extraction industrially uses both amalgamation (Au dissolves in Hg to form amalgam, then Hg is distilled off) and the cyanide process (ore treated with dilute NaCN in the presence of air, forming soluble [Au(CN)2]⁻, which is then precipitated by zinc). Both methods are employed commercially.
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