Question
Chemistry Question on d -and f -Block Elements
If Cu2+ ions is treated with excess of KCN, the complex formed is
A
K2[Cu(CN)4]
B
K3[Cu(CN)4]
C
K4[Cu(CN)6]
D
All of these
Answer
K3[Cu(CN)4]
Explanation
Solution
Cu2+ is reduced to Cu+ which forms complex K3[Cu(CN)4] 2CuSO4+10KCN→2K3[Cu(CN)4]+2K2SO4+(CN)2