Question

Calculate the number of electrons in $16$ gm $O^{2-}$.

Answer 1

16 gm oxygen is equal to 1 mole and by Avogadro's number 1 mole of any gas contains $6.023\times {10}^{23}$ atoms.

1 atom of oxygen has 8 electrons

$\therefore 6.023\times {10}^{23}$ atoms have $8\times 6.023\times {10}^{23}$ electrons

$=48.184\times {10}^{23}$ electrons