Atomic mass of Na = 23u (Given)
Then, gram atomic mass of Na = 23g
Now, 23g of Na contains `= 6.022×10^(23)g`
number of atoms
Thus, 100g of Na contains `= 6.022×10^(23)// 23xx100` number of atoms
`= 2.6182 × 10^(24)` number of atoms
Again, atomic mass of Fe = 56u (Given)
Then, gram atomic mass of Fe = 56g
Now, 56 g of Fe contains `= 6.022×10^(23)`
number of atoms
Thus, 100g of Fe contains `= 6.022xx10^(23)//56xx100` number of atoms
`= 1.0753 × 10^(24)` number of atoms
Therefore, 100 grams of sodium contain more number of atoms than 100 grams of iron