D-And F-Block Elements Ques 183
Question: Copper sulphate solution reacts with $ KCN $ to give
[MP PMT 1992; MNR 1994; IIT 1996; AIIMS 1999; CBSE PMT 2002]
Options:
A) $ Cu{{(CN)}_2} $
B) $ CuCN $
C) $ K_2[Cu{{(CN)}_4}] $
D) $ K_3[Cu{{(CN)}_4}] $
Show Answer
Answer:
Correct Answer: D
Solution:
$ CuSO_4+2KCN\to Cu{{(CN)}_2}+K_2SO_4 $
$ 2Cu{{(CN)}_2}\to Cu_2{{(CN)}_2}+{{(CN)}_2} $
$ Cu_2{{(CN)}_2}+6KCN\to 2K_3[Cu{{(CN)}_4}] $