A) \[Cu{{(CN)}_{2}}\]
B) \[CuCN\]
C) \[{{K}_{2}}[Cu{{(CN)}_{4}}]\]
D) \[{{K}_{3}}[Cu{{(CN)}_{4}}]\]
Correct Answer: D
Solution :
Copper sulphate when reacts with KCN first gives precipitate of cupric cyanide which reduces into\[C{{u}_{2}}C{{N}_{2}}\]and dissolves in excess of KCN to give soluble \[{{K}_{3}}[Cu{{(CN)}_{4}}]\]complex salt. \[\underset{(Cupric\,cyanide)}{\mathop{[CuS{{O}_{4}}+2KCN\to Cu{{(CN)}_{2}}+{{K}_{2}}S{{O}_{4}}]\times 2}}\,\] \[2Cu{{(CN)}_{2}}\to C{{u}_{2}}{{(CN)}_{2}}+\underset{cyanogen}{\mathop{NC-CN}}\,\] \[\frac{C{{u}_{2}}{{(CN)}_{2}}+6KCN\to \underset{So\operatorname{lub}le\,complex\,salt}{\mathop{2{{K}_{3}}[Cu{{(CN)}_{4}}]}}\,}{2CuS{{O}_{4}}+10KCN\to 2{{K}_{3}}[Cu{{(CN)}_{4}}]+2{{K}_{2}}S{{O}_{4}}+{{(CN)}_{2}}}\]
You need to login to perform this action.
You will be redirected in
3 sec
