Question

Gold is extracted by making soluble cyanide complex. The cyanide complex is ______.

विकल्प

• [Au(CN)₄]⁻

• [Au(CN)₂]⁻

• [Au(CN)₃]⁻

• [Au(CN)]⁻

Answer 1

Gold is extracted by making soluble cyanide complex. The cyanide complex is [Au(CN)₂]⁻.

Explanation:

\[\ce{4Au + 8 KCN + 2H2O + O2 -> \underset{Soluble}{4K [Au(CN)2]} + 4KOH}\]