(A) If we add ferric chloride over potassium ferrocyanide, it forms a white precipitate that will become blue.
The reaction is :
+| 3K4[Fe(CN)6] |
| Potassiumferrocyanide |
⟶| Fe4[Fe(CN)6]3 |
| White(I)precipitate |
+ This is normal reaction because being small quantity of ferric chloride, not all potassium is displaced. (B) Aqueous zinc chloride
(ZnCl2) reacts with aqueous hydroxide
(NaOH) to produce zinc hydroxide
[Zn(OH)2] and
NaCl. Therefore, zinc hydroxide is dissolved when excess
NaOH is added to the precipitate.
(C) Yellow coloured ferric chloride reacts with hydrogen sulphide to form green coloured ferrous chloride.
In this reaction, ferric chloride is reduced and
H2S is oxidised.
+⟶| 2FeCl2 |
| Ferrouschloride(green)(II) |
+S Hence, correct match is
A→1,B→5,C→2