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What is obtained when a freshly precipitated $\;Fe(OH)_{3}\;$ is shaken with title amount of dilute solution of $\;Fecl_{3}\;$ ?

$\begin{array}{1 1} \text{(a) A reddish brown colloidal solution of} \;Fe(OH_{2})_{3} \\ \text{ (b) A bluish colloidal solution of}\;Fecl_{3} \\ \text{(c) A reddish brown colloidal solution of}\;Fe(OH)_{3} \\ (d) \text{A brown solution of} \;Fe_{2}(OH)_{3} \end{array}$

Answer : A reddish brown colloidal solution of $\;Fe(OH)_{3}$
Explanation :
When a freshly precipitated $\;Fe(OH)_{3}\;$ is shaken with little amount of dilute solution of $\;Fecl_{3}\;$ , a reddish brown colloidal solution of $\;Fe(OH)_{3}\;$ is obtained . This process is called peptization .
The $\;Fe^{3+}\;$ ions from $\;Fecl_{3}\;$ are adsorbed on the surface of the precipitate and form positively charged colloidal solution .
$Fecl_{3} \to Fe^{3+} +3cl^{-}$
$Fe(OH)_{3}+Fe^{3+}\;[Fe(OH)_{3}] Fe^{3+}+3cl^{-}\;$ colloidal solution