ChemistryEasy99×since 2002Q1359Leaching of gold with dilute aqueous solution of NaCN in presence of oxygen gives complex [A], which on reaction with zinc forms the elemental gold and another complex [B]. [A] and [B], respectively are :A[Au(CN)4]−{[Au{(CN)_4}]^ - }[Au(CN)4]− and [Zn(CN)2(OH)2]2−{[Zn{(CN)_2}{(OH)_2}]^{2 - }}[Zn(CN)2(OH)2]2−B[Au(CN)2]−{[Au{(CN)_2}]^ - }[Au(CN)2]− and [Zn(OH)4]2−{[Zn{(OH)_4}]^{2 - }}[Zn(OH)4]2−C[Au(CN)2]−{[Au{(CN)_2}]^{ - }}[Au(CN)2]− and [Zn(CN)4]2−{[Zn{(CN)_4}]^{2 - }}[Zn(CN)4]2−D[Au(CN)4]2−{[Au{(CN)_4}]^{2 - }}[Au(CN)4]2− and [Zn(CN)6]4−{[Zn{(CN)_6}]^{4 - }}[Zn(CN)6]4−Check answerSkip