Question

Ferric iodide is very unstable but ferric chloride is a stable compound. This is because

• A. hydration energy of ferric iodide is less than that of ferric chloride
• B. $I^{-}$ ion is a stronger reducing agent as compared to $C{l}^{-}$ ion and thus, $F{e}^{3+}$ is easily reduced by $I^{-}$ ion to $F{e}^{2+}$ ion.
• C. ferric iodide is a covalent compound whereas ferric chloride is ionic
• D. ferric iodide is a covalent compound whereas ferric chloride is ionic

Answer 1

The correct option is B $I^{-}$ ion is a stronger reducing agent as compared to $C{l}^{-}$ ion and thus, $F{e}^{3+}$ is easily reduced by $I^{-}$ ion to $F{e}^{2+}$ ion.

$2F{e}^{3+}+2I^{-}⟶2F{e}^{2+}+I_2$