`FeCl_3 + K_4[Fe(CN)_6] to` ?

Options

A. Brown ring complex
B. Sodium nitroprusside
C. Turnbull's blue
D. Prussian blue

Answer

To solve the reaction between FeCl₃ and K₄[Fe(CN)₆], we will follow these steps:

### Step 1: Identify the Reactants
We have two reactants:
- Ferric chloride (FeCl₃)
- Potassium ferrocyanide (K₄[Fe(CN)₆])

### Step 2: Write the Reaction
When FeCl₃ reacts with K₄[Fe(CN)₆], the iron (III) ions from FeCl₃ will react with the ferrocyanide ions from K₄[Fe(CN)₆] to form a complex.

### Step 3: Determine the Products
The product formed from this reaction is ferric ferrocyanide, which is represented as Fe₃[Fe(CN)₆]₂. Additionally, potassium chloride (KCl) will also be formed as a byproduct.

### Step 4: Balance the Reaction
To balance the reaction, we need to ensure that the number of each type of atom is the same on both sides of the equation. The balanced equation will be:
\[ 3 \text{FeCl}_3 + 2 \text{K}_4[\text{Fe(CN)}_6] \rightarrow \text{Fe}_3[\text{Fe(CN)}_6]_2 + 6 \text{KCl} \]

### Step 5: Identify the Color of the Complex
The complex formed, ferric ferrocyanide, is known to produce a characteristic color known as "Persian blue."

### Final Answer
The reaction of FeCl₃ with K₄[Fe(CN)₆] produces ferric ferrocyanide (Fe₃[Fe(CN)₆]₂) and potassium chloride (KCl), with the complex exhibiting a Persian blue color.

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