The difference between 100 moles of sodium and sodium ions is 5.48002g. Calculate the mass of an electron.

Sodium loses an electron to form sodium ions.
Na → $N{a}^{+}$ + $e^{-}$

Sodium atom loses an electron to form sodium ion.

1 mole of Sodium atom has the difference of 1 electron.

So, 100 moles of Sodium atoms will have the difference of 100 electrons.

For 100 moles of each sodium atom and sodium ion, there would be a difference of 100 moles of electrons.

One mole of electrons has $6.023\times {10}^{23}{e}^{-}$
Given that,Mass of 100 moles of electron = 5.48002g
Mass of 1 mole of electron = (5.48002/100)g
Mass of 1 electron = 5.48002/(100×$6.023\times {10}^{23}{e}^{-}$ ) = $9.1\times {10}^{-28}g$ or $9.1\times {10}^{-31}kg$