Question

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

• A. lattice energy of ferric iodide is less then that of ferric chloride
• B. Weak bonding exists between $F{e}^{3+}$ and $I^{-}$ions
• C. ferric iodide is a covalent compounds wherese ferric chloride is ionic
• D. $I^{-1}$ion is a stronger reducing agent as compered to $C{l}^{-}$ion and thus, $F{e}^{3+}$ is easily reducd by $I^{-}$ion to $F{e}^{3+}$ion

Answer 1

Answer: (D)

$I^{-1}$ion is a stronger reducing agent as compered to $C{l}^{-}$ion and thus, $F{e}^{3+}$ is easily reducd by $I^{-}$ion to $F{e}^{3+}$ion

$I^{-}$ is a stronger reducing agent than $C{l}^{-}$ ion. Hence, $F{e}^{3+}$ ion is easily reduced by $I^{-}$ ion to $F{e}^{2+}$ ion and itself gets oxidized to $I_2$.

But, this does not happen in case of $FeC{l}_3$. Hence, $FeC{l}_3$ is stable but $Fe{I}_3$ is unstable.

$2F{e}^{3+}+2I^{-}⟶2F{e}^{2+}+I_2$