Question

The Total number of electrons present in 48 g Mg^2+ are?

Answer 1

24 g of Mg contains N_A atoms.

$N_A = 6.023 \times 10^{23}$

1 atom of Mg contains 12 electrons.

Mg2+ ion contains (12-2) = 10 electrons.

2NA Mg2+ ions contain $10 \times 2N_A = 20N_A \;electrons$