Question

Total no. of electrons present in $48$ g of $M{g}^{2+}$ are:

• A. $24N_A$
• B. $2N_A$
• C. $20N_A$
• D. None of these

Answer 1

The correct option is C $20N_A$

$24gm$ of magnesium contains $N_A$ atoms.

$\therefore 48gm$ magnesium contains$=2N_A$ atoms

$M{g}^{2+}$ ion contain $=12-2=10$ electrons

Hence, $2N_A$ $M{g}^{2+}$ ions will contain $=10\times 2N_A=20N_A$ electrons