Question

The oxidation state of Fe in K$_4$[Fe(CN)$_6$] is

• A. +2
• B. +3
• C. 0
• D. +4

Hint:

In coordination compounds, the oxidation state of the central metal can be determined by balancing the charges from ligands and counterions.

Answer 1

The Correct Option is A

Step 1: Understand the formula.
K$_4$[Fe(CN)$_6$] is a coordination compound. The cyanide ion (CN$^-$) has a charge of -1, and there are 6 cyanide ions in the complex, giving a total charge of -6.
Step 2: Calculate the oxidation state of Fe.
The overall charge of the complex is neutral, so the oxidation state of Fe must balance the charge of the cyanide ions and the 4 potassium ions. - Potassium (K) has a +1 charge, and there are 4 potassium ions, so the total charge from K is +4. - The total charge from the cyanide ions is -6. Thus, to balance the charges, the oxidation state of Fe must be +2.
Step 3: Apply to the options.
The oxidation state of Fe in K$_4$[Fe(CN)$_6$] is +2, so the correct answer is (A).
Final Answer: \[ \boxed{+2} \]