avogadro's constant is the number of atoms of carbon-12 in 12g of
carbon-12.
atoms present equals avogadro's constant times number of moles for that substance. Type of substance does not change the number of atoms if you are given the quantity of moles, therefore the fact that it is sodium does not change the value.
atoms present equals avogadro's constant times number of moles
=6.023x10^23 x 4.0
=2.4x10^24
