1)

For the given aqueous reaction which of the statement(s) is (are) true?

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A) The first reaction is a redox reaction

B) White precipitate is $Zn_{3}[Fe(CN)_{6}]_{2}$

C) Addition of filtrate to starch solution gives blue colour

D) white precipitate is soluble in NaOH solution

Answer:

Option A,C,D

Explanation:

$K_{3}[Fe^{3+}(CN)_{6}]+KI(excess) $  $\rightarrow$

                        $K_{4}[Fe^{+2}(CN)_{6}]+KI_{3}$ (redxox)( Brownish yellow solution)

 $K_{4}[Fe(CN)_{6}]+ZnSO_{4}$ $ \rightarrow$

$ K_{2}Zn_{3}[Fe(CN)_{6}]_{2}$ or $K_{2}Zn[Fe(CN)_{6}]$ (white ppt)

 $I_{3}^{-}$(Brownish yellow filtrate)+$2Na_{2}S_{2}O_{3}$ $\rightarrow$   $Na_{2}S_{4}O_{6}$(clear solution)+2NaI+$I_{2}$ (Turns strach solution blue)

 $K_{2}Zn[Fe(CN)_{6}]$ react with NaOH as

  $K_{2}Zn[Fe(CN)_{6}]+NaOH$  $ \rightarrow$  $ [Zn(OH)_{4}]^{2-}+[Fe(CN)_{6}]^{4-}$