Question

The solution of $K_4\left[Fe\right(CN{)}_6]$ in water will

• A. give a test for $K^{+}$
• B. give a test for $F{e}^{2+}$
• C. give a test for $C{N}^{-}$
• D. none of the above

Answer 1

The correct option is A give a test for $K^{+}$

Double salts are generally made up of 2 or more salts and when dissolved in water, dissociate totally into individual ions, there by loosing the identity as a double salt. Whereas in complex compounds, the coordination sphere does not break due to very strong intermolecular forces. It does not dissociate into simple ions and thus, it retain its identity.

Hence, $K_4\left[Fe\right(CN{)}_6]$ will dissociate as $K^{+}$ and $\left[Fe\right(CN{)}_6{]}^{4-}$
Thus, the solution will give test only for $K^{+}$.
Hence, option (a) is correct.