Question

$M{g}^{2+}$ ion has how many number of electrons?

• A. $12$
• B. $10$
• C. $14$
• D. $24$

Answer 1

Answer: (B)

$10$

The atomic number of $Mg$ is $12$. Mg has $12$ electrons. $Mg$ loses two electrons to form $M{g}^{2+}$ ion.
$Mg\to M{g}^{2+}+2e^{-}$
The number of electrons in $M{g}^{2+}$ ion will be $12-2=10$