`3KCN+Fe(CN)_(3)darr to K_(3)[Fe(CN)_(6)]`

Options

A. For coloured ppt./Black ppt
B. For coloured solution.
C. for clear/colourless solution
D. For white ppt.

Answer

To solve the given reaction \(3KCN + Fe(CN)_3 \rightarrow K_3[Fe(CN)_6]\) and determine the nature of the product, we can follow these steps:

### Step 1: Identify the reactants and products
- The reactants are potassium cyanide (KCN) and iron(III) cyanide (Fe(CN)₃).
- The product is potassium hexacyanoferrate(III), represented as \(K_3[Fe(CN)_6]\).

### Step 2: Analyze the reaction
- In this reaction, three moles of KCN react with one mole of Fe(CN)₃ to form one mole of \(K_3[Fe(CN)_6]\).
- This indicates that KCN is acting as a ligand that coordinates with the iron ion in Fe(CN)₃.

### Step 3: Determine the solubility of the product
- The product \(K_3[Fe(CN)_6]\) is a complex ion that is soluble in water.
- Since it is soluble, it will not form a precipitate.

### Step 4: Identify the oxidation state of iron in the product
- In \(K_3[Fe(CN)_6]\), the iron is in the +3 oxidation state (Fe³⁺).
- The oxidation state can be determined by considering the overall charge of the complex and the charge contributed by the cyanide ions (CN⁻).

### Step 5: Determine the color of the solution
- The color of the solution is influenced by the oxidation state of iron.
- Iron in the +3 oxidation state (Fe³⁺) typically imparts a yellow color to the solution.

### Conclusion
- The reaction produces a colored solution, specifically a yellow solution, due to the presence of the Fe³⁺ ion in the complex.

### Final Answer
- The reaction \(3KCN + Fe(CN)_3 \rightarrow K_3[Fe(CN)_6]\) results in a yellow colored solution.

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