Question

which has more atoms,50g of aluminum or 50g of iron (AL =27u , Fe=56u)

Answer 1

Calculation for the number of atoms:
Aluminium:
Atomic mass = 27 g/mol
27g of aluminium contains = 6.022 $\times$ 10²³ atoms
So, 50g of aluminium will contain = $\frac{6.022\times {10}^{23}}{27}\times 50=1.11\times {10}^{24}$ atoms

Iron
Atomic mass = 56 g/ mol
56​g of iron contains = 6.022 $\times$ 10²³ atoms
So, 50g of iron will contain = $\frac{6.022\times {10}^{23}}{56}\times 50=5.37\times {10}^{23}$ atoms

Hence, 50g of aluminium contains more number of atoms than 50g of iron.