Question

$Mg^{2+}$ is isoelectronic with

• A. $Ca^{2+}$
• B. $Na^{+}$
• C. $Zn^{2+}$
• D. $Cu^{2+}$

Answer 1

Answer: (B)

Isoelectronic species have same number of electron. $Mg ^{2+}$ and $Na ^{+}$ both have 10 electrons hence, they are isoelectronic species.