Analytical ChemistryHard
Question
Co2+ + KCN (not in excess) → precipitate.
Select the correct statement(s) with respect to the precipitate.
Select the correct statement(s) with respect to the precipitate.
Options
A.It is yellow in colour.
B.It is reddish-brown in colour.
C.It dissolves in excess of the reagent forming a brown solution.
D.It is obtained when brown solution (option (C)) is acidified with dilute HCl in the cold.
Solution
Co2+ + 2CN- → Co(CN)2↓ (reddish - brown)
Co(CN)2 ↓ + 4CN- (excess) → [Co(CN)6]4- (brown solution)
[Co(CN)6]4- + 4H+ → Co(CN)2 ↓ + 4HCN.
Co(CN)2 ↓ + 4CN- (excess) → [Co(CN)6]4- (brown solution)
[Co(CN)6]4- + 4H+ → Co(CN)2 ↓ + 4HCN.
Create a free account to view solution
View Solution FreeMore Analytical Chemistry Questions
Which of the following sulphides do not dissolve in 50% HNO3 but dissolve in aquaregia ?...A coloured solution of a salt gives following reactions.(i) It gives white precipitate with sodium hydroxide which becom...A mixture of chlorides of copper, cadmium, chromium, iron and aluminium was dissolved in water. It was acidified with di...Which one of the following statements is correct?...The carbonate of which of the following cation is soluble in water ?...