Analytical Chemistry Question 64
Question: Which of the following change the colour of the aqueous solution of $ FeCl_3 $
[Roorkee Qualifying 1998]
Options:
A) $ K_4[ Fe{{( CN )}_6} ] $
B) $ H_2S $
C) $ NH_4CNS $
D) $ KCNS $
Show Answer
Answer:
Correct Answer: A
Solution:
$ FeCl_3+K_4[ Fe{{(CN)}_6} ]\to \underset{\text{Ferri ferrocyanide (Blue)}}{\mathop{Fe_4{{[ Fe{{(CN)}_6} ]}_3}}} $
$ 2FeCl_3+3H_2S\to Fe_2S_3+6HCl $
$ 3NH_4CNS+FeCl_3\underset{(Blood\ red)}{\mathop{\to Fe{{(CNS)}_3}+}} $
$ 3NH_4Cl $
$ FeCl_3+3KCNS\to \underset{(\text{Blood red)}}{\mathop{Fe{{(CNS)}_3}}} $ +3KCl
BETA
