Question

The stability sequence of divalent cations in the formation of chelates is:
(A). \( \text{Cu}^{2+} \)
(B). \( \text{Ni}^{2+} \)
(C). \( \text{Co}^{2+} \)
(D). \( \text{Zn}^{2+} \)
Choose the correct answer from the options given below:

• A. (A), (B), (C), (D).
• B. (A), (C), (D), (B).
• C. (B), (A), (D), (C).
• D. (C), (B), (D), (A).

Hint:

To easily remember the Irving-Williams series:
Copper (\( \text{Cu}^{2+} \)) always forms the most stable complexes among the common divalent micronutrient cations, followed by Nickel (\( \text{Ni}^{2+} \)).
This hierarchy is driven by crystal field stabilization energy and ionic radius contraction.

Answer 1

The Correct Option is A