Q.:- Which has more number of atoms, 100 grams of sodium or 100 grams of iron (given atomic mass of Na = 23 u, Fe = 56 u) ?
Answer:-
100 g of sodium:
Number of sodium atoms

= 2.62 x 1024 atoms.
100 g of iron :
Number of iron atoms

= 1.07 x 1024 atoms
Thus, 100 g of sodium has more atoms.