What will be the oxidation number of Fe in `K_(3)[Fe(CN)_(6)]` :-

Options

A. `+4`
B. `+3`
C. `+2`
D. Zero

Answer

To determine the oxidation number of iron (Fe) in the compound \( K_3[Fe(CN)_6] \), we can follow these steps:

### Step 1: Identify the components of the compound
The compound consists of potassium ions (K) and a complex ion \([Fe(CN)_6]^{3-}\).

### Step 2: Assign oxidation numbers to known elements
- The oxidation number of potassium (K) is \( +1 \).
- The oxidation number of the cyanide ion (CN) is \( -1 \).

### Step 3: Set up the equation
Let the oxidation number of iron (Fe) be \( x \). The complex ion \([Fe(CN)_6]\) has a total charge of \( -3 \) (since the overall charge of the compound is neutral and there are three potassium ions contributing \( +3 \)).

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

### Step 4: Simplify the equation
Substituting the known values into the equation:
\[ 3 + x - 6 = 0 \]

### Step 5: Solve for \( x \)
Now, simplify the equation:
\[ x - 3 = 0 \]
\[ x = +3 \]

### Conclusion
The oxidation number of iron (Fe) in \( K_3[Fe(CN)_6] \) is \( +3 \).

### Final Answer
The oxidation number of Fe is \( +3 \).

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