Question

The pair, in which ions are isoelectronic with $Al^{3+}$ is:

• A. Br– and Be2+
• B. Cl– and Li+
• C. S2– and K+
• D. O2– and Mg2+

Answer 1

Answer: (D)

O2– and Mg2+

Answer 2

O2–, Mg2+ and Al3+ are isoelectronic. All have 10 electrons.

So, the correct option is (D): O2– and Mg2+