Question

Which from following cations will form most stable complex with same ligand?

• A. \(\mathrm{Cu}^{2+}\)
• B. \(\mathrm{Co}^{2+}\)
• C. \(\mathrm{Mn}^{2+}\)
• D. \(\mathrm{Fe}^{2+}\)

Hint:

Use the Irving-Williams series for stability of complexes of divalent first-row transition metal ions.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept
For divalent ions of the first transition series, stability of complexes with the same ligand follows the Irving-Williams order.

Step 2: Order
\(\text{Mn}^{2+}<\text{Fe}^{2+}<\text{Co}^{2+}<\text{Ni}^{2+}<\text{Cu}^{2+}>\text{Zn}^{2+}\).

Step 3: Result
Among the options, \(\text{Cu}^{2+}\) forms the most stable complex.

Final Answer:
\(\text{Cu}^{2+}\) forms the most stable complex. \[ \boxed{\text{(A) }\mathrm{Cu}^{2+}} \]