The oxidation number of iron in potassium ferricyanide `[K_(3)Fe(CN)_(6)]` is :-

Options

A. Two
B. Six
C. Three
D. Four

Answer

To determine the oxidation number of iron (Fe) in potassium ferricyanide \([K_3Fe(CN)_6]\), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Components**:
The formula of potassium ferricyanide is \([K_3Fe(CN)_6]\). It consists of potassium (K), iron (Fe), and cyanide (CN).

2. **Assign Known Oxidation Numbers**:
- The oxidation number of potassium (K) is \(+1\).
- The oxidation number of cyanide (CN) is \(-1\).

3. **Set Up the Equation**:
Let the oxidation number of iron (Fe) be \(x\). The compound is neutral, so the sum of the oxidation numbers must equal zero.

The equation can be set up as follows:
\[ 3(+1) + x + 6(-1) = 0 \]

4. **Simplify the Equation**:
Substitute the known values into the equation:
\[ 3 + x - 6 = 0 \]

5. **Solve for \(x\)**:
Rearranging the equation gives:
\[ x - 3 = 0 \]
Therefore,
\[ x = 3 \]

6. **Conclusion**:
The oxidation number of iron (Fe) in potassium ferricyanide \([K_3Fe(CN)_6]\) is \(+3\).

### Final Answer:
The oxidation number of iron in potassium ferricyanide \([K_3Fe(CN)_6]\) is \(+3\).

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